Search
Find a vulnerability
Search criteria
ⓘ
Use this form to refine search results.
Full-text search supports keyword queries with ranking and filtering.
You can combine vendor, product, and sources to narrow results.
Enable “Apply ordering” to sort by date instead of relevance.
6 vulnerabilities found for Linux kernel by Ubuntu
CVE-2021-3493 (GCVE-0-2021-3493)
Vulnerability from cvelistv5 – Published: 2021-04-17 04:20 – Updated: 2025-10-21 23:25Summary
The overlayfs implementation in the linux kernel did not properly validate with respect to user namespaces the setting of file capabilities on files in an underlying file system. Due to the combination of unprivileged user namespaces along with a patch carried in the Ubuntu kernel to allow unprivileged overlay mounts, an attacker could use this to gain elevated privileges.
Severity
8.8 (High)
SSVC
Exploitation: active
Automatable: no
Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
- CWE-270 - Privilege Context Switching Error
Assigner
References
7 references
| URL | Tags |
|---|---|
| https://ubuntu.com/security/notices/USN-4917-1 | x_refsource_MISC |
| https://git.kernel.org/pub/scm/linux/kernel/git/t… | x_refsource_MISC |
| https://www.openwall.com/lists/oss-security/2021/… | x_refsource_MISC |
| http://packetstormsecurity.com/files/162434/Kerne… | x_refsource_MISC |
| http://packetstormsecurity.com/files/162866/Ubunt… | x_refsource_MISC |
| http://packetstormsecurity.com/files/165151/Ubunt… | x_refsource_MISC |
| https://www.cisa.gov/known-exploited-vulnerabilit… | government-resource |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| Ubuntu | linux kernel |
Affected:
5.8 kernel , < 5.8.0-50.56
(custom)
Affected: 5.4 kernel , < 5.4.0-72.80 (custom) Affected: 4.15 kernel , < 4.15.0-142.146 (custom) Affected: 4.4 kernel , < 4.4.0-209.241 (custom) |
Date Public
2021-04-15 00:00
Credits
{
"containers": {
"adp": [
{
"providerMetadata": {
"dateUpdated": "2024-08-03T16:53:17.827Z",
"orgId": "af854a3a-2127-422b-91ae-364da2661108",
"shortName": "CVE"
},
"references": [
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://ubuntu.com/security/notices/USN-4917-1"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c03e2cda4a584cadc398e8f6641ca9988a39d52"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://www.openwall.com/lists/oss-security/2021/04/16/1"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "http://packetstormsecurity.com/files/162434/Kernel-Live-Patch-Security-Notice-LSN-0076-1.html"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "http://packetstormsecurity.com/files/162866/Ubuntu-OverlayFS-Local-Privilege-Escalation.html"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "http://packetstormsecurity.com/files/165151/Ubuntu-Overlayfs-Local-Privilege-Escalation.html"
}
],
"title": "CVE Program Container"
},
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2021-3493",
"options": [
{
"Exploitation": "active"
},
{
"Automatable": "no"
},
{
"Technical Impact": "total"
}
],
"role": "CISA Coordinator",
"timestamp": "2025-02-07T12:30:18.913674Z",
"version": "2.0.3"
},
"type": "ssvc"
}
},
{
"other": {
"content": {
"dateAdded": "2022-10-20",
"reference": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-3493"
},
"type": "kev"
}
}
],
"providerMetadata": {
"dateUpdated": "2025-10-21T23:25:48.908Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"references": [
{
"tags": [
"government-resource"
],
"url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-3493"
}
],
"timeline": [
{
"lang": "en",
"time": "2022-10-20T00:00:00.000Z",
"value": "CVE-2021-3493 added to CISA KEV"
}
],
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"product": "linux kernel",
"vendor": "Ubuntu",
"versions": [
{
"lessThan": "5.8.0-50.56",
"status": "affected",
"version": "5.8 kernel",
"versionType": "custom"
},
{
"lessThan": "5.4.0-72.80",
"status": "affected",
"version": "5.4 kernel",
"versionType": "custom"
},
{
"lessThan": "4.15.0-142.146",
"status": "affected",
"version": "4.15 kernel",
"versionType": "custom"
},
{
"lessThan": "4.4.0-209.241",
"status": "affected",
"version": "4.4 kernel",
"versionType": "custom"
}
]
}
],
"credits": [
{
"lang": "en",
"value": "An independent security researcher reporting to the SSD Secure Disclosure program"
}
],
"datePublic": "2021-04-15T00:00:00.000Z",
"descriptions": [
{
"lang": "en",
"value": "The overlayfs implementation in the linux kernel did not properly validate with respect to user namespaces the setting of file capabilities on files in an underlying file system. Due to the combination of unprivileged user namespaces along with a patch carried in the Ubuntu kernel to allow unprivileged overlay mounts, an attacker could use this to gain elevated privileges."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 8.8,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "CHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
"version": "3.1"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-270",
"description": "CWE-270: Privilege Context Switching Error",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2021-12-03T19:06:06.000Z",
"orgId": "cc1ad9ee-3454-478d-9317-d3e869d708bc",
"shortName": "canonical"
},
"references": [
{
"tags": [
"x_refsource_MISC"
],
"url": "https://ubuntu.com/security/notices/USN-4917-1"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c03e2cda4a584cadc398e8f6641ca9988a39d52"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "https://www.openwall.com/lists/oss-security/2021/04/16/1"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "http://packetstormsecurity.com/files/162434/Kernel-Live-Patch-Security-Notice-LSN-0076-1.html"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "http://packetstormsecurity.com/files/162866/Ubuntu-OverlayFS-Local-Privilege-Escalation.html"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "http://packetstormsecurity.com/files/165151/Ubuntu-Overlayfs-Local-Privilege-Escalation.html"
}
],
"solutions": [
{
"lang": "en",
"value": "Apply https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c03e2cda4a584cadc398e8f6641ca9988a39d52"
}
],
"source": {
"discovery": "EXTERNAL"
},
"workarounds": [
{
"lang": "en",
"value": "Disable unprivileged user namespaces."
}
],
"x_generator": {
"engine": "Vulnogram 0.0.9"
},
"x_legacyV4Record": {
"CVE_data_meta": {
"ASSIGNER": "security@ubuntu.com",
"DATE_PUBLIC": "2021-04-15T00:00:00.000Z",
"ID": "CVE-2021-3493",
"STATE": "PUBLIC"
},
"affects": {
"vendor": {
"vendor_data": [
{
"product": {
"product_data": [
{
"product_name": "linux kernel",
"version": {
"version_data": [
{
"version_affected": "\u003c",
"version_name": "5.8 kernel",
"version_value": "5.8.0-50.56"
},
{
"version_affected": "\u003c",
"version_name": "5.4 kernel",
"version_value": "5.4.0-72.80"
},
{
"version_affected": "\u003c",
"version_name": "4.15 kernel",
"version_value": "4.15.0-142.146"
},
{
"version_affected": "\u003c",
"version_name": "4.4 kernel",
"version_value": "4.4.0-209.241"
}
]
}
}
]
},
"vendor_name": "Ubuntu"
}
]
}
},
"credit": [
{
"lang": "eng",
"value": "An independent security researcher reporting to the SSD Secure Disclosure program"
}
],
"data_format": "MITRE",
"data_type": "CVE",
"data_version": "4.0",
"description": {
"description_data": [
{
"lang": "eng",
"value": "The overlayfs implementation in the linux kernel did not properly validate with respect to user namespaces the setting of file capabilities on files in an underlying file system. Due to the combination of unprivileged user namespaces along with a patch carried in the Ubuntu kernel to allow unprivileged overlay mounts, an attacker could use this to gain elevated privileges."
}
]
},
"generator": {
"engine": "Vulnogram 0.0.9"
},
"impact": {
"cvss": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 8.8,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "CHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
"version": "3.1"
}
},
"problemtype": {
"problemtype_data": [
{
"description": [
{
"lang": "eng",
"value": "CWE-270: Privilege Context Switching Error"
}
]
}
]
},
"references": {
"reference_data": [
{
"name": "https://ubuntu.com/security/notices/USN-4917-1",
"refsource": "MISC",
"url": "https://ubuntu.com/security/notices/USN-4917-1"
},
{
"name": "https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c03e2cda4a584cadc398e8f6641ca9988a39d52",
"refsource": "MISC",
"url": "https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c03e2cda4a584cadc398e8f6641ca9988a39d52"
},
{
"name": "https://www.openwall.com/lists/oss-security/2021/04/16/1",
"refsource": "MISC",
"url": "https://www.openwall.com/lists/oss-security/2021/04/16/1"
},
{
"name": "http://packetstormsecurity.com/files/162434/Kernel-Live-Patch-Security-Notice-LSN-0076-1.html",
"refsource": "MISC",
"url": "http://packetstormsecurity.com/files/162434/Kernel-Live-Patch-Security-Notice-LSN-0076-1.html"
},
{
"name": "http://packetstormsecurity.com/files/162866/Ubuntu-OverlayFS-Local-Privilege-Escalation.html",
"refsource": "MISC",
"url": "http://packetstormsecurity.com/files/162866/Ubuntu-OverlayFS-Local-Privilege-Escalation.html"
},
{
"name": "http://packetstormsecurity.com/files/165151/Ubuntu-Overlayfs-Local-Privilege-Escalation.html",
"refsource": "MISC",
"url": "http://packetstormsecurity.com/files/165151/Ubuntu-Overlayfs-Local-Privilege-Escalation.html"
}
]
},
"solution": [
{
"lang": "en",
"value": "Apply https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c03e2cda4a584cadc398e8f6641ca9988a39d52"
}
],
"source": {
"discovery": "EXTERNAL"
},
"work_around": [
{
"lang": "en",
"value": "Disable unprivileged user namespaces."
}
]
}
}
},
"cveMetadata": {
"assignerOrgId": "cc1ad9ee-3454-478d-9317-d3e869d708bc",
"assignerShortName": "canonical",
"cveId": "CVE-2021-3493",
"datePublished": "2021-04-17T04:20:16.706Z",
"dateReserved": "2021-04-12T00:00:00.000Z",
"dateUpdated": "2025-10-21T23:25:48.908Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.1"
}
CVE-2021-3492 (GCVE-0-2021-3492)
Vulnerability from cvelistv5 – Published: 2021-04-17 04:20 – Updated: 2024-09-17 03:54
VLAI
Title
Ubuntu linux kernel shiftfs file system double free vulnerability
Summary
Shiftfs, an out-of-tree stacking file system included in Ubuntu Linux kernels, did not properly handle faults occurring during copy_from_user() correctly. These could lead to either a double-free situation or memory not being freed at all. An attacker could use this to cause a denial of service (kernel memory exhaustion) or gain privileges via executing arbitrary code. AKA ZDI-CAN-13562.
Severity
8.8 (High)
Assigner
References
6 references
| URL | Tags |
|---|---|
| https://www.openwall.com/lists/oss-security/2021/… | x_refsource_MISC |
| https://git.launchpad.net/~ubuntu-kernel/ubuntu/+… | x_refsource_MISC |
| https://git.launchpad.net/~ubuntu-kernel/ubuntu/+… | x_refsource_MISC |
| https://ubuntu.com/security/notices/USN-4917-1 | x_refsource_MISC |
| https://www.zerodayinitiative.com/advisories/ZDI-… | x_refsource_MISC |
| http://packetstormsecurity.com/files/162614/Kerne… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| Ubuntu | Linux kernel |
Affected:
5.8 kernel , < 5.8.0-50.56
(custom)
Affected: 5.4 kernel , < 5.4.0-72.80 (custom) |
Date Public
2021-04-15 00:00
Credits
{
"containers": {
"adp": [
{
"providerMetadata": {
"dateUpdated": "2024-08-03T16:53:17.692Z",
"orgId": "af854a3a-2127-422b-91ae-364da2661108",
"shortName": "CVE"
},
"references": [
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://www.openwall.com/lists/oss-security/2021/04/16/2"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=8fee52ab9da87d82bc6de9ebb3480fff9b4d53e6"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=25c891a949bf918b59cbc6e4932015ba4c35c333"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://ubuntu.com/security/notices/USN-4917-1"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://www.zerodayinitiative.com/advisories/ZDI-21-422/"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "http://packetstormsecurity.com/files/162614/Kernel-Live-Patch-Security-Notice-LSN-0077-1.html"
}
],
"title": "CVE Program Container"
}
],
"cna": {
"affected": [
{
"product": "Linux kernel",
"vendor": "Ubuntu",
"versions": [
{
"lessThan": "5.8.0-50.56",
"status": "affected",
"version": "5.8 kernel",
"versionType": "custom"
},
{
"lessThan": "5.4.0-72.80",
"status": "affected",
"version": "5.4 kernel",
"versionType": "custom"
}
]
}
],
"credits": [
{
"lang": "en",
"value": "Vincent Dehors of Synactiv Digital Security"
}
],
"datePublic": "2021-04-15T00:00:00.000Z",
"descriptions": [
{
"lang": "en",
"value": "Shiftfs, an out-of-tree stacking file system included in Ubuntu Linux kernels, did not properly handle faults occurring during copy_from_user() correctly. These could lead to either a double-free situation or memory not being freed at all. An attacker could use this to cause a denial of service (kernel memory exhaustion) or gain privileges via executing arbitrary code. AKA ZDI-CAN-13562."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 8.8,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "CHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
"version": "3.1"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-415",
"description": "CWE-415: Double Free",
"lang": "en",
"type": "CWE"
}
]
},
{
"descriptions": [
{
"cweId": "CWE-401",
"description": "CWE-401: Missing Release of Memory after Effective Lifetime",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2021-05-18T17:06:14.000Z",
"orgId": "cc1ad9ee-3454-478d-9317-d3e869d708bc",
"shortName": "canonical"
},
"references": [
{
"tags": [
"x_refsource_MISC"
],
"url": "https://www.openwall.com/lists/oss-security/2021/04/16/2"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=8fee52ab9da87d82bc6de9ebb3480fff9b4d53e6"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=25c891a949bf918b59cbc6e4932015ba4c35c333"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "https://ubuntu.com/security/notices/USN-4917-1"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "https://www.zerodayinitiative.com/advisories/ZDI-21-422/"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "http://packetstormsecurity.com/files/162614/Kernel-Live-Patch-Security-Notice-LSN-0077-1.html"
}
],
"source": {
"discovery": "EXTERNAL"
},
"title": "Ubuntu linux kernel shiftfs file system double free vulnerability",
"x_generator": {
"engine": "Vulnogram 0.0.9"
},
"x_legacyV4Record": {
"CVE_data_meta": {
"ASSIGNER": "security@ubuntu.com",
"DATE_PUBLIC": "2021-04-15T00:00:00.000Z",
"ID": "CVE-2021-3492",
"STATE": "PUBLIC",
"TITLE": "Ubuntu linux kernel shiftfs file system double free vulnerability"
},
"affects": {
"vendor": {
"vendor_data": [
{
"product": {
"product_data": [
{
"product_name": "Linux kernel",
"version": {
"version_data": [
{
"version_affected": "\u003c",
"version_name": "5.8 kernel",
"version_value": "5.8.0-50.56"
},
{
"version_affected": "\u003c",
"version_name": "5.4 kernel",
"version_value": "5.4.0-72.80"
}
]
}
}
]
},
"vendor_name": "Ubuntu"
}
]
}
},
"credit": [
{
"lang": "eng",
"value": "Vincent Dehors of Synactiv Digital Security"
}
],
"data_format": "MITRE",
"data_type": "CVE",
"data_version": "4.0",
"description": {
"description_data": [
{
"lang": "eng",
"value": "Shiftfs, an out-of-tree stacking file system included in Ubuntu Linux kernels, did not properly handle faults occurring during copy_from_user() correctly. These could lead to either a double-free situation or memory not being freed at all. An attacker could use this to cause a denial of service (kernel memory exhaustion) or gain privileges via executing arbitrary code. AKA ZDI-CAN-13562."
}
]
},
"generator": {
"engine": "Vulnogram 0.0.9"
},
"impact": {
"cvss": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 8.8,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "CHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
"version": "3.1"
}
},
"problemtype": {
"problemtype_data": [
{
"description": [
{
"lang": "eng",
"value": "CWE-415: Double Free"
}
]
},
{
"description": [
{
"lang": "eng",
"value": "CWE-401: Missing Release of Memory after Effective Lifetime"
}
]
}
]
},
"references": {
"reference_data": [
{
"name": "https://www.openwall.com/lists/oss-security/2021/04/16/2",
"refsource": "MISC",
"url": "https://www.openwall.com/lists/oss-security/2021/04/16/2"
},
{
"name": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=8fee52ab9da87d82bc6de9ebb3480fff9b4d53e6",
"refsource": "MISC",
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=8fee52ab9da87d82bc6de9ebb3480fff9b4d53e6"
},
{
"name": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=25c891a949bf918b59cbc6e4932015ba4c35c333",
"refsource": "MISC",
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=25c891a949bf918b59cbc6e4932015ba4c35c333"
},
{
"name": "https://ubuntu.com/security/notices/USN-4917-1",
"refsource": "MISC",
"url": "https://ubuntu.com/security/notices/USN-4917-1"
},
{
"name": "https://www.zerodayinitiative.com/advisories/ZDI-21-422/",
"refsource": "MISC",
"url": "https://www.zerodayinitiative.com/advisories/ZDI-21-422/"
},
{
"name": "http://packetstormsecurity.com/files/162614/Kernel-Live-Patch-Security-Notice-LSN-0077-1.html",
"refsource": "MISC",
"url": "http://packetstormsecurity.com/files/162614/Kernel-Live-Patch-Security-Notice-LSN-0077-1.html"
}
]
},
"source": {
"discovery": "EXTERNAL"
}
}
}
},
"cveMetadata": {
"assignerOrgId": "cc1ad9ee-3454-478d-9317-d3e869d708bc",
"assignerShortName": "canonical",
"cveId": "CVE-2021-3492",
"datePublished": "2021-04-17T04:20:16.011Z",
"dateReserved": "2021-04-09T00:00:00.000Z",
"dateUpdated": "2024-09-17T03:54:52.527Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.1"
}
CVE-2019-15794 (GCVE-0-2019-15794)
Vulnerability from cvelistv5 – Published: 2020-04-23 23:55 – Updated: 2024-09-16 19:52
VLAI
Title
Reference counting error in overlayfs/shiftfs error path when used in conjuction with aufs
Summary
Overlayfs in the Linux kernel and shiftfs, a non-upstream patch to the Linux kernel included in the Ubuntu 5.0 and 5.3 kernel series, both replace vma->vm_file in their mmap handlers. On error the original value is not restored, and the reference is put for the file to which vm_file points. On upstream kernels this is not an issue, as no callers dereference vm_file following after call_mmap() returns an error. However, the aufs patchs change mmap_region() to replace the fput() using a local variable with vma_fput(), which will fput() vm_file, leading to a refcount underflow.
Severity
7.1 (High)
CWE
- CWE-672 - Operation on a Resource after Expiration or Release
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://git.launchpad.net/~ubuntu-kernel/ubuntu/+… | x_refsource_MISC |
| https://git.launchpad.net/~ubuntu-kernel/ubuntu/+… | x_refsource_MISC |
| https://usn.ubuntu.com/usn/usn-4208-1 | x_refsource_MISC |
| https://usn.ubuntu.com/usn/usn-4209-1 | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| Ubuntu | Linux kernel |
Affected:
5.3 kernel , < 5.3.0-24.26
(custom)
Affected: 5.0 kernel , < 5.0.0-37.40 (custom) |
Date Public
2019-11-08 00:00
Credits
{
"containers": {
"adp": [
{
"providerMetadata": {
"dateUpdated": "2024-08-05T00:56:22.473Z",
"orgId": "af854a3a-2127-422b-91ae-364da2661108",
"shortName": "CVE"
},
"references": [
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=270d16ae48a4dbf1c7e25e94cc3e38b4bea37635"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=ef81780548d20a786cc77ed4203fca146fd81ce3"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://usn.ubuntu.com/usn/usn-4208-1"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://usn.ubuntu.com/usn/usn-4209-1"
}
],
"title": "CVE Program Container"
}
],
"cna": {
"affected": [
{
"product": "Linux kernel",
"vendor": "Ubuntu",
"versions": [
{
"lessThan": "5.3.0-24.26",
"status": "affected",
"version": "5.3 kernel",
"versionType": "custom"
},
{
"lessThan": "5.0.0-37.40",
"status": "affected",
"version": "5.0 kernel",
"versionType": "custom"
}
]
}
],
"credits": [
{
"lang": "en",
"value": "Jann Horn of Google Project Zero"
}
],
"datePublic": "2019-11-08T00:00:00.000Z",
"descriptions": [
{
"lang": "en",
"value": "Overlayfs in the Linux kernel and shiftfs, a non-upstream patch to the Linux kernel included in the Ubuntu 5.0 and 5.3 kernel series, both replace vma-\u003evm_file in their mmap handlers. On error the original value is not restored, and the reference is put for the file to which vm_file points. On upstream kernels this is not an issue, as no callers dereference vm_file following after call_mmap() returns an error. However, the aufs patchs change mmap_region() to replace the fput() using a local variable with vma_fput(), which will fput() vm_file, leading to a refcount underflow."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 7.1,
"baseSeverity": "HIGH",
"confidentialityImpact": "NONE",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H",
"version": "3.1"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-672",
"description": "CWE-672 Operation on a Resource after Expiration or Release",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2020-04-23T23:55:24.000Z",
"orgId": "cc1ad9ee-3454-478d-9317-d3e869d708bc",
"shortName": "canonical"
},
"references": [
{
"tags": [
"x_refsource_MISC"
],
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=270d16ae48a4dbf1c7e25e94cc3e38b4bea37635"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=ef81780548d20a786cc77ed4203fca146fd81ce3"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "https://usn.ubuntu.com/usn/usn-4208-1"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "https://usn.ubuntu.com/usn/usn-4209-1"
}
],
"source": {
"defect": [
"https://bugs.launchpad.net/bugs/1850994"
],
"discovery": "EXTERNAL"
},
"title": "Reference counting error in overlayfs/shiftfs error path when used in conjuction with aufs",
"x_generator": {
"engine": "Vulnogram 0.0.9"
},
"x_legacyV4Record": {
"CVE_data_meta": {
"ASSIGNER": "security@ubuntu.com",
"DATE_PUBLIC": "2019-11-08T00:00:00.000Z",
"ID": "CVE-2019-15794",
"STATE": "PUBLIC",
"TITLE": "Reference counting error in overlayfs/shiftfs error path when used in conjuction with aufs"
},
"affects": {
"vendor": {
"vendor_data": [
{
"product": {
"product_data": [
{
"product_name": "Linux kernel",
"version": {
"version_data": [
{
"version_affected": "\u003c",
"version_name": "5.3 kernel",
"version_value": "5.3.0-24.26"
},
{
"version_affected": "\u003c",
"version_name": "5.0 kernel",
"version_value": "5.0.0-37.40"
}
]
}
}
]
},
"vendor_name": "Ubuntu"
}
]
}
},
"credit": [
{
"lang": "eng",
"value": "Jann Horn of Google Project Zero"
}
],
"data_format": "MITRE",
"data_type": "CVE",
"data_version": "4.0",
"description": {
"description_data": [
{
"lang": "eng",
"value": "Overlayfs in the Linux kernel and shiftfs, a non-upstream patch to the Linux kernel included in the Ubuntu 5.0 and 5.3 kernel series, both replace vma-\u003evm_file in their mmap handlers. On error the original value is not restored, and the reference is put for the file to which vm_file points. On upstream kernels this is not an issue, as no callers dereference vm_file following after call_mmap() returns an error. However, the aufs patchs change mmap_region() to replace the fput() using a local variable with vma_fput(), which will fput() vm_file, leading to a refcount underflow."
}
]
},
"generator": {
"engine": "Vulnogram 0.0.9"
},
"impact": {
"cvss": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 7.1,
"baseSeverity": "HIGH",
"confidentialityImpact": "NONE",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H",
"version": "3.1"
}
},
"problemtype": {
"problemtype_data": [
{
"description": [
{
"lang": "eng",
"value": "CWE-672 Operation on a Resource after Expiration or Release"
}
]
}
]
},
"references": {
"reference_data": [
{
"name": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=270d16ae48a4dbf1c7e25e94cc3e38b4bea37635",
"refsource": "MISC",
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=270d16ae48a4dbf1c7e25e94cc3e38b4bea37635"
},
{
"name": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=ef81780548d20a786cc77ed4203fca146fd81ce3",
"refsource": "MISC",
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=ef81780548d20a786cc77ed4203fca146fd81ce3"
},
{
"name": "https://usn.ubuntu.com/usn/usn-4208-1",
"refsource": "MISC",
"url": "https://usn.ubuntu.com/usn/usn-4208-1"
},
{
"name": "https://usn.ubuntu.com/usn/usn-4209-1",
"refsource": "MISC",
"url": "https://usn.ubuntu.com/usn/usn-4209-1"
}
]
},
"source": {
"defect": [
"https://bugs.launchpad.net/bugs/1850994"
],
"discovery": "EXTERNAL"
}
}
}
},
"cveMetadata": {
"assignerOrgId": "cc1ad9ee-3454-478d-9317-d3e869d708bc",
"assignerShortName": "canonical",
"cveId": "CVE-2019-15794",
"datePublished": "2020-04-23T23:55:25.039Z",
"dateReserved": "2019-08-29T00:00:00.000Z",
"dateUpdated": "2024-09-16T19:52:18.313Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.1"
}
CVE-2021-3492 (GCVE-0-2021-3492)
Vulnerability from nvd – Published: 2021-04-17 04:20 – Updated: 2024-09-17 03:54
VLAI
Title
Ubuntu linux kernel shiftfs file system double free vulnerability
Summary
Shiftfs, an out-of-tree stacking file system included in Ubuntu Linux kernels, did not properly handle faults occurring during copy_from_user() correctly. These could lead to either a double-free situation or memory not being freed at all. An attacker could use this to cause a denial of service (kernel memory exhaustion) or gain privileges via executing arbitrary code. AKA ZDI-CAN-13562.
Severity
8.8 (High)
Assigner
References
6 references
| URL | Tags |
|---|---|
| https://www.openwall.com/lists/oss-security/2021/… | x_refsource_MISC |
| https://git.launchpad.net/~ubuntu-kernel/ubuntu/+… | x_refsource_MISC |
| https://git.launchpad.net/~ubuntu-kernel/ubuntu/+… | x_refsource_MISC |
| https://ubuntu.com/security/notices/USN-4917-1 | x_refsource_MISC |
| https://www.zerodayinitiative.com/advisories/ZDI-… | x_refsource_MISC |
| http://packetstormsecurity.com/files/162614/Kerne… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| Ubuntu | Linux kernel |
Affected:
5.8 kernel , < 5.8.0-50.56
(custom)
Affected: 5.4 kernel , < 5.4.0-72.80 (custom) |
Date Public
2021-04-15 00:00
Credits
{
"containers": {
"adp": [
{
"providerMetadata": {
"dateUpdated": "2024-08-03T16:53:17.692Z",
"orgId": "af854a3a-2127-422b-91ae-364da2661108",
"shortName": "CVE"
},
"references": [
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://www.openwall.com/lists/oss-security/2021/04/16/2"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=8fee52ab9da87d82bc6de9ebb3480fff9b4d53e6"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=25c891a949bf918b59cbc6e4932015ba4c35c333"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://ubuntu.com/security/notices/USN-4917-1"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://www.zerodayinitiative.com/advisories/ZDI-21-422/"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "http://packetstormsecurity.com/files/162614/Kernel-Live-Patch-Security-Notice-LSN-0077-1.html"
}
],
"title": "CVE Program Container"
}
],
"cna": {
"affected": [
{
"product": "Linux kernel",
"vendor": "Ubuntu",
"versions": [
{
"lessThan": "5.8.0-50.56",
"status": "affected",
"version": "5.8 kernel",
"versionType": "custom"
},
{
"lessThan": "5.4.0-72.80",
"status": "affected",
"version": "5.4 kernel",
"versionType": "custom"
}
]
}
],
"credits": [
{
"lang": "en",
"value": "Vincent Dehors of Synactiv Digital Security"
}
],
"datePublic": "2021-04-15T00:00:00.000Z",
"descriptions": [
{
"lang": "en",
"value": "Shiftfs, an out-of-tree stacking file system included in Ubuntu Linux kernels, did not properly handle faults occurring during copy_from_user() correctly. These could lead to either a double-free situation or memory not being freed at all. An attacker could use this to cause a denial of service (kernel memory exhaustion) or gain privileges via executing arbitrary code. AKA ZDI-CAN-13562."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 8.8,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "CHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
"version": "3.1"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-415",
"description": "CWE-415: Double Free",
"lang": "en",
"type": "CWE"
}
]
},
{
"descriptions": [
{
"cweId": "CWE-401",
"description": "CWE-401: Missing Release of Memory after Effective Lifetime",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2021-05-18T17:06:14.000Z",
"orgId": "cc1ad9ee-3454-478d-9317-d3e869d708bc",
"shortName": "canonical"
},
"references": [
{
"tags": [
"x_refsource_MISC"
],
"url": "https://www.openwall.com/lists/oss-security/2021/04/16/2"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=8fee52ab9da87d82bc6de9ebb3480fff9b4d53e6"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=25c891a949bf918b59cbc6e4932015ba4c35c333"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "https://ubuntu.com/security/notices/USN-4917-1"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "https://www.zerodayinitiative.com/advisories/ZDI-21-422/"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "http://packetstormsecurity.com/files/162614/Kernel-Live-Patch-Security-Notice-LSN-0077-1.html"
}
],
"source": {
"discovery": "EXTERNAL"
},
"title": "Ubuntu linux kernel shiftfs file system double free vulnerability",
"x_generator": {
"engine": "Vulnogram 0.0.9"
},
"x_legacyV4Record": {
"CVE_data_meta": {
"ASSIGNER": "security@ubuntu.com",
"DATE_PUBLIC": "2021-04-15T00:00:00.000Z",
"ID": "CVE-2021-3492",
"STATE": "PUBLIC",
"TITLE": "Ubuntu linux kernel shiftfs file system double free vulnerability"
},
"affects": {
"vendor": {
"vendor_data": [
{
"product": {
"product_data": [
{
"product_name": "Linux kernel",
"version": {
"version_data": [
{
"version_affected": "\u003c",
"version_name": "5.8 kernel",
"version_value": "5.8.0-50.56"
},
{
"version_affected": "\u003c",
"version_name": "5.4 kernel",
"version_value": "5.4.0-72.80"
}
]
}
}
]
},
"vendor_name": "Ubuntu"
}
]
}
},
"credit": [
{
"lang": "eng",
"value": "Vincent Dehors of Synactiv Digital Security"
}
],
"data_format": "MITRE",
"data_type": "CVE",
"data_version": "4.0",
"description": {
"description_data": [
{
"lang": "eng",
"value": "Shiftfs, an out-of-tree stacking file system included in Ubuntu Linux kernels, did not properly handle faults occurring during copy_from_user() correctly. These could lead to either a double-free situation or memory not being freed at all. An attacker could use this to cause a denial of service (kernel memory exhaustion) or gain privileges via executing arbitrary code. AKA ZDI-CAN-13562."
}
]
},
"generator": {
"engine": "Vulnogram 0.0.9"
},
"impact": {
"cvss": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 8.8,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "CHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
"version": "3.1"
}
},
"problemtype": {
"problemtype_data": [
{
"description": [
{
"lang": "eng",
"value": "CWE-415: Double Free"
}
]
},
{
"description": [
{
"lang": "eng",
"value": "CWE-401: Missing Release of Memory after Effective Lifetime"
}
]
}
]
},
"references": {
"reference_data": [
{
"name": "https://www.openwall.com/lists/oss-security/2021/04/16/2",
"refsource": "MISC",
"url": "https://www.openwall.com/lists/oss-security/2021/04/16/2"
},
{
"name": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=8fee52ab9da87d82bc6de9ebb3480fff9b4d53e6",
"refsource": "MISC",
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=8fee52ab9da87d82bc6de9ebb3480fff9b4d53e6"
},
{
"name": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=25c891a949bf918b59cbc6e4932015ba4c35c333",
"refsource": "MISC",
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=25c891a949bf918b59cbc6e4932015ba4c35c333"
},
{
"name": "https://ubuntu.com/security/notices/USN-4917-1",
"refsource": "MISC",
"url": "https://ubuntu.com/security/notices/USN-4917-1"
},
{
"name": "https://www.zerodayinitiative.com/advisories/ZDI-21-422/",
"refsource": "MISC",
"url": "https://www.zerodayinitiative.com/advisories/ZDI-21-422/"
},
{
"name": "http://packetstormsecurity.com/files/162614/Kernel-Live-Patch-Security-Notice-LSN-0077-1.html",
"refsource": "MISC",
"url": "http://packetstormsecurity.com/files/162614/Kernel-Live-Patch-Security-Notice-LSN-0077-1.html"
}
]
},
"source": {
"discovery": "EXTERNAL"
}
}
}
},
"cveMetadata": {
"assignerOrgId": "cc1ad9ee-3454-478d-9317-d3e869d708bc",
"assignerShortName": "canonical",
"cveId": "CVE-2021-3492",
"datePublished": "2021-04-17T04:20:16.011Z",
"dateReserved": "2021-04-09T00:00:00.000Z",
"dateUpdated": "2024-09-17T03:54:52.527Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.1"
}
CVE-2021-3493 (GCVE-0-2021-3493)
Vulnerability from nvd – Published: 2021-04-17 04:20 – Updated: 2025-10-21 23:25Summary
The overlayfs implementation in the linux kernel did not properly validate with respect to user namespaces the setting of file capabilities on files in an underlying file system. Due to the combination of unprivileged user namespaces along with a patch carried in the Ubuntu kernel to allow unprivileged overlay mounts, an attacker could use this to gain elevated privileges.
Severity
8.8 (High)
SSVC
Exploitation: active
Automatable: no
Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
- CWE-270 - Privilege Context Switching Error
Assigner
References
7 references
| URL | Tags |
|---|---|
| https://ubuntu.com/security/notices/USN-4917-1 | x_refsource_MISC |
| https://git.kernel.org/pub/scm/linux/kernel/git/t… | x_refsource_MISC |
| https://www.openwall.com/lists/oss-security/2021/… | x_refsource_MISC |
| http://packetstormsecurity.com/files/162434/Kerne… | x_refsource_MISC |
| http://packetstormsecurity.com/files/162866/Ubunt… | x_refsource_MISC |
| http://packetstormsecurity.com/files/165151/Ubunt… | x_refsource_MISC |
| https://www.cisa.gov/known-exploited-vulnerabilit… | government-resource |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| Ubuntu | linux kernel |
Affected:
5.8 kernel , < 5.8.0-50.56
(custom)
Affected: 5.4 kernel , < 5.4.0-72.80 (custom) Affected: 4.15 kernel , < 4.15.0-142.146 (custom) Affected: 4.4 kernel , < 4.4.0-209.241 (custom) |
Date Public
2021-04-15 00:00
Credits
{
"containers": {
"adp": [
{
"providerMetadata": {
"dateUpdated": "2024-08-03T16:53:17.827Z",
"orgId": "af854a3a-2127-422b-91ae-364da2661108",
"shortName": "CVE"
},
"references": [
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://ubuntu.com/security/notices/USN-4917-1"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c03e2cda4a584cadc398e8f6641ca9988a39d52"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://www.openwall.com/lists/oss-security/2021/04/16/1"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "http://packetstormsecurity.com/files/162434/Kernel-Live-Patch-Security-Notice-LSN-0076-1.html"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "http://packetstormsecurity.com/files/162866/Ubuntu-OverlayFS-Local-Privilege-Escalation.html"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "http://packetstormsecurity.com/files/165151/Ubuntu-Overlayfs-Local-Privilege-Escalation.html"
}
],
"title": "CVE Program Container"
},
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2021-3493",
"options": [
{
"Exploitation": "active"
},
{
"Automatable": "no"
},
{
"Technical Impact": "total"
}
],
"role": "CISA Coordinator",
"timestamp": "2025-02-07T12:30:18.913674Z",
"version": "2.0.3"
},
"type": "ssvc"
}
},
{
"other": {
"content": {
"dateAdded": "2022-10-20",
"reference": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-3493"
},
"type": "kev"
}
}
],
"providerMetadata": {
"dateUpdated": "2025-10-21T23:25:48.908Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"references": [
{
"tags": [
"government-resource"
],
"url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-3493"
}
],
"timeline": [
{
"lang": "en",
"time": "2022-10-20T00:00:00.000Z",
"value": "CVE-2021-3493 added to CISA KEV"
}
],
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"product": "linux kernel",
"vendor": "Ubuntu",
"versions": [
{
"lessThan": "5.8.0-50.56",
"status": "affected",
"version": "5.8 kernel",
"versionType": "custom"
},
{
"lessThan": "5.4.0-72.80",
"status": "affected",
"version": "5.4 kernel",
"versionType": "custom"
},
{
"lessThan": "4.15.0-142.146",
"status": "affected",
"version": "4.15 kernel",
"versionType": "custom"
},
{
"lessThan": "4.4.0-209.241",
"status": "affected",
"version": "4.4 kernel",
"versionType": "custom"
}
]
}
],
"credits": [
{
"lang": "en",
"value": "An independent security researcher reporting to the SSD Secure Disclosure program"
}
],
"datePublic": "2021-04-15T00:00:00.000Z",
"descriptions": [
{
"lang": "en",
"value": "The overlayfs implementation in the linux kernel did not properly validate with respect to user namespaces the setting of file capabilities on files in an underlying file system. Due to the combination of unprivileged user namespaces along with a patch carried in the Ubuntu kernel to allow unprivileged overlay mounts, an attacker could use this to gain elevated privileges."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 8.8,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "CHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
"version": "3.1"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-270",
"description": "CWE-270: Privilege Context Switching Error",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2021-12-03T19:06:06.000Z",
"orgId": "cc1ad9ee-3454-478d-9317-d3e869d708bc",
"shortName": "canonical"
},
"references": [
{
"tags": [
"x_refsource_MISC"
],
"url": "https://ubuntu.com/security/notices/USN-4917-1"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c03e2cda4a584cadc398e8f6641ca9988a39d52"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "https://www.openwall.com/lists/oss-security/2021/04/16/1"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "http://packetstormsecurity.com/files/162434/Kernel-Live-Patch-Security-Notice-LSN-0076-1.html"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "http://packetstormsecurity.com/files/162866/Ubuntu-OverlayFS-Local-Privilege-Escalation.html"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "http://packetstormsecurity.com/files/165151/Ubuntu-Overlayfs-Local-Privilege-Escalation.html"
}
],
"solutions": [
{
"lang": "en",
"value": "Apply https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c03e2cda4a584cadc398e8f6641ca9988a39d52"
}
],
"source": {
"discovery": "EXTERNAL"
},
"workarounds": [
{
"lang": "en",
"value": "Disable unprivileged user namespaces."
}
],
"x_generator": {
"engine": "Vulnogram 0.0.9"
},
"x_legacyV4Record": {
"CVE_data_meta": {
"ASSIGNER": "security@ubuntu.com",
"DATE_PUBLIC": "2021-04-15T00:00:00.000Z",
"ID": "CVE-2021-3493",
"STATE": "PUBLIC"
},
"affects": {
"vendor": {
"vendor_data": [
{
"product": {
"product_data": [
{
"product_name": "linux kernel",
"version": {
"version_data": [
{
"version_affected": "\u003c",
"version_name": "5.8 kernel",
"version_value": "5.8.0-50.56"
},
{
"version_affected": "\u003c",
"version_name": "5.4 kernel",
"version_value": "5.4.0-72.80"
},
{
"version_affected": "\u003c",
"version_name": "4.15 kernel",
"version_value": "4.15.0-142.146"
},
{
"version_affected": "\u003c",
"version_name": "4.4 kernel",
"version_value": "4.4.0-209.241"
}
]
}
}
]
},
"vendor_name": "Ubuntu"
}
]
}
},
"credit": [
{
"lang": "eng",
"value": "An independent security researcher reporting to the SSD Secure Disclosure program"
}
],
"data_format": "MITRE",
"data_type": "CVE",
"data_version": "4.0",
"description": {
"description_data": [
{
"lang": "eng",
"value": "The overlayfs implementation in the linux kernel did not properly validate with respect to user namespaces the setting of file capabilities on files in an underlying file system. Due to the combination of unprivileged user namespaces along with a patch carried in the Ubuntu kernel to allow unprivileged overlay mounts, an attacker could use this to gain elevated privileges."
}
]
},
"generator": {
"engine": "Vulnogram 0.0.9"
},
"impact": {
"cvss": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 8.8,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "CHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
"version": "3.1"
}
},
"problemtype": {
"problemtype_data": [
{
"description": [
{
"lang": "eng",
"value": "CWE-270: Privilege Context Switching Error"
}
]
}
]
},
"references": {
"reference_data": [
{
"name": "https://ubuntu.com/security/notices/USN-4917-1",
"refsource": "MISC",
"url": "https://ubuntu.com/security/notices/USN-4917-1"
},
{
"name": "https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c03e2cda4a584cadc398e8f6641ca9988a39d52",
"refsource": "MISC",
"url": "https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c03e2cda4a584cadc398e8f6641ca9988a39d52"
},
{
"name": "https://www.openwall.com/lists/oss-security/2021/04/16/1",
"refsource": "MISC",
"url": "https://www.openwall.com/lists/oss-security/2021/04/16/1"
},
{
"name": "http://packetstormsecurity.com/files/162434/Kernel-Live-Patch-Security-Notice-LSN-0076-1.html",
"refsource": "MISC",
"url": "http://packetstormsecurity.com/files/162434/Kernel-Live-Patch-Security-Notice-LSN-0076-1.html"
},
{
"name": "http://packetstormsecurity.com/files/162866/Ubuntu-OverlayFS-Local-Privilege-Escalation.html",
"refsource": "MISC",
"url": "http://packetstormsecurity.com/files/162866/Ubuntu-OverlayFS-Local-Privilege-Escalation.html"
},
{
"name": "http://packetstormsecurity.com/files/165151/Ubuntu-Overlayfs-Local-Privilege-Escalation.html",
"refsource": "MISC",
"url": "http://packetstormsecurity.com/files/165151/Ubuntu-Overlayfs-Local-Privilege-Escalation.html"
}
]
},
"solution": [
{
"lang": "en",
"value": "Apply https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c03e2cda4a584cadc398e8f6641ca9988a39d52"
}
],
"source": {
"discovery": "EXTERNAL"
},
"work_around": [
{
"lang": "en",
"value": "Disable unprivileged user namespaces."
}
]
}
}
},
"cveMetadata": {
"assignerOrgId": "cc1ad9ee-3454-478d-9317-d3e869d708bc",
"assignerShortName": "canonical",
"cveId": "CVE-2021-3493",
"datePublished": "2021-04-17T04:20:16.706Z",
"dateReserved": "2021-04-12T00:00:00.000Z",
"dateUpdated": "2025-10-21T23:25:48.908Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.1"
}
CVE-2019-15794 (GCVE-0-2019-15794)
Vulnerability from nvd – Published: 2020-04-23 23:55 – Updated: 2024-09-16 19:52
VLAI
Title
Reference counting error in overlayfs/shiftfs error path when used in conjuction with aufs
Summary
Overlayfs in the Linux kernel and shiftfs, a non-upstream patch to the Linux kernel included in the Ubuntu 5.0 and 5.3 kernel series, both replace vma->vm_file in their mmap handlers. On error the original value is not restored, and the reference is put for the file to which vm_file points. On upstream kernels this is not an issue, as no callers dereference vm_file following after call_mmap() returns an error. However, the aufs patchs change mmap_region() to replace the fput() using a local variable with vma_fput(), which will fput() vm_file, leading to a refcount underflow.
Severity
7.1 (High)
CWE
- CWE-672 - Operation on a Resource after Expiration or Release
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://git.launchpad.net/~ubuntu-kernel/ubuntu/+… | x_refsource_MISC |
| https://git.launchpad.net/~ubuntu-kernel/ubuntu/+… | x_refsource_MISC |
| https://usn.ubuntu.com/usn/usn-4208-1 | x_refsource_MISC |
| https://usn.ubuntu.com/usn/usn-4209-1 | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| Ubuntu | Linux kernel |
Affected:
5.3 kernel , < 5.3.0-24.26
(custom)
Affected: 5.0 kernel , < 5.0.0-37.40 (custom) |
Date Public
2019-11-08 00:00
Credits
{
"containers": {
"adp": [
{
"providerMetadata": {
"dateUpdated": "2024-08-05T00:56:22.473Z",
"orgId": "af854a3a-2127-422b-91ae-364da2661108",
"shortName": "CVE"
},
"references": [
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=270d16ae48a4dbf1c7e25e94cc3e38b4bea37635"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=ef81780548d20a786cc77ed4203fca146fd81ce3"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://usn.ubuntu.com/usn/usn-4208-1"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://usn.ubuntu.com/usn/usn-4209-1"
}
],
"title": "CVE Program Container"
}
],
"cna": {
"affected": [
{
"product": "Linux kernel",
"vendor": "Ubuntu",
"versions": [
{
"lessThan": "5.3.0-24.26",
"status": "affected",
"version": "5.3 kernel",
"versionType": "custom"
},
{
"lessThan": "5.0.0-37.40",
"status": "affected",
"version": "5.0 kernel",
"versionType": "custom"
}
]
}
],
"credits": [
{
"lang": "en",
"value": "Jann Horn of Google Project Zero"
}
],
"datePublic": "2019-11-08T00:00:00.000Z",
"descriptions": [
{
"lang": "en",
"value": "Overlayfs in the Linux kernel and shiftfs, a non-upstream patch to the Linux kernel included in the Ubuntu 5.0 and 5.3 kernel series, both replace vma-\u003evm_file in their mmap handlers. On error the original value is not restored, and the reference is put for the file to which vm_file points. On upstream kernels this is not an issue, as no callers dereference vm_file following after call_mmap() returns an error. However, the aufs patchs change mmap_region() to replace the fput() using a local variable with vma_fput(), which will fput() vm_file, leading to a refcount underflow."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 7.1,
"baseSeverity": "HIGH",
"confidentialityImpact": "NONE",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H",
"version": "3.1"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-672",
"description": "CWE-672 Operation on a Resource after Expiration or Release",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2020-04-23T23:55:24.000Z",
"orgId": "cc1ad9ee-3454-478d-9317-d3e869d708bc",
"shortName": "canonical"
},
"references": [
{
"tags": [
"x_refsource_MISC"
],
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=270d16ae48a4dbf1c7e25e94cc3e38b4bea37635"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=ef81780548d20a786cc77ed4203fca146fd81ce3"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "https://usn.ubuntu.com/usn/usn-4208-1"
},
{
"tags": [
"x_refsource_MISC"
],
"url": "https://usn.ubuntu.com/usn/usn-4209-1"
}
],
"source": {
"defect": [
"https://bugs.launchpad.net/bugs/1850994"
],
"discovery": "EXTERNAL"
},
"title": "Reference counting error in overlayfs/shiftfs error path when used in conjuction with aufs",
"x_generator": {
"engine": "Vulnogram 0.0.9"
},
"x_legacyV4Record": {
"CVE_data_meta": {
"ASSIGNER": "security@ubuntu.com",
"DATE_PUBLIC": "2019-11-08T00:00:00.000Z",
"ID": "CVE-2019-15794",
"STATE": "PUBLIC",
"TITLE": "Reference counting error in overlayfs/shiftfs error path when used in conjuction with aufs"
},
"affects": {
"vendor": {
"vendor_data": [
{
"product": {
"product_data": [
{
"product_name": "Linux kernel",
"version": {
"version_data": [
{
"version_affected": "\u003c",
"version_name": "5.3 kernel",
"version_value": "5.3.0-24.26"
},
{
"version_affected": "\u003c",
"version_name": "5.0 kernel",
"version_value": "5.0.0-37.40"
}
]
}
}
]
},
"vendor_name": "Ubuntu"
}
]
}
},
"credit": [
{
"lang": "eng",
"value": "Jann Horn of Google Project Zero"
}
],
"data_format": "MITRE",
"data_type": "CVE",
"data_version": "4.0",
"description": {
"description_data": [
{
"lang": "eng",
"value": "Overlayfs in the Linux kernel and shiftfs, a non-upstream patch to the Linux kernel included in the Ubuntu 5.0 and 5.3 kernel series, both replace vma-\u003evm_file in their mmap handlers. On error the original value is not restored, and the reference is put for the file to which vm_file points. On upstream kernels this is not an issue, as no callers dereference vm_file following after call_mmap() returns an error. However, the aufs patchs change mmap_region() to replace the fput() using a local variable with vma_fput(), which will fput() vm_file, leading to a refcount underflow."
}
]
},
"generator": {
"engine": "Vulnogram 0.0.9"
},
"impact": {
"cvss": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 7.1,
"baseSeverity": "HIGH",
"confidentialityImpact": "NONE",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H",
"version": "3.1"
}
},
"problemtype": {
"problemtype_data": [
{
"description": [
{
"lang": "eng",
"value": "CWE-672 Operation on a Resource after Expiration or Release"
}
]
}
]
},
"references": {
"reference_data": [
{
"name": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=270d16ae48a4dbf1c7e25e94cc3e38b4bea37635",
"refsource": "MISC",
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=270d16ae48a4dbf1c7e25e94cc3e38b4bea37635"
},
{
"name": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=ef81780548d20a786cc77ed4203fca146fd81ce3",
"refsource": "MISC",
"url": "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=ef81780548d20a786cc77ed4203fca146fd81ce3"
},
{
"name": "https://usn.ubuntu.com/usn/usn-4208-1",
"refsource": "MISC",
"url": "https://usn.ubuntu.com/usn/usn-4208-1"
},
{
"name": "https://usn.ubuntu.com/usn/usn-4209-1",
"refsource": "MISC",
"url": "https://usn.ubuntu.com/usn/usn-4209-1"
}
]
},
"source": {
"defect": [
"https://bugs.launchpad.net/bugs/1850994"
],
"discovery": "EXTERNAL"
}
}
}
},
"cveMetadata": {
"assignerOrgId": "cc1ad9ee-3454-478d-9317-d3e869d708bc",
"assignerShortName": "canonical",
"cveId": "CVE-2019-15794",
"datePublished": "2020-04-23T23:55:25.039Z",
"dateReserved": "2019-08-29T00:00:00.000Z",
"dateUpdated": "2024-09-16T19:52:18.313Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.1"
}