CVE-2021-33645 (GCVE-0-2021-33645)
Vulnerability from cvelistv5 – Published: 2022-08-09 00:00 – Updated: 2025-11-03 20:33
VLAI
EPSS
VEX
Summary
The th_read() function doesn’t free a variable t->th_buf.gnu_longlink after allocating memory, which may cause a memory leak.
Severity
7.5 (High)
CWE
- CWE-401 - Missing Release of Memory after Effective Lifetime
Assigner
References
7 references
| URL | Tags |
|---|---|
| https://www.openeuler.org/en/security/safety-bull… | |
| https://lists.fedoraproject.org/archives/list/pac… | vendor-advisory |
| https://lists.fedoraproject.org/archives/list/pac… | vendor-advisory |
| https://lists.fedoraproject.org/archives/list/pac… | vendor-advisory |
| https://lists.fedoraproject.org/archives/list/pac… | vendor-advisory |
| https://lists.fedoraproject.org/archives/list/pac… | vendor-advisory |
| https://lists.debian.org/debian-lts-announce/2025… |
{
"containers": {
"adp": [
{
"providerMetadata": {
"dateUpdated": "2025-11-03T20:33:38.619Z",
"orgId": "af854a3a-2127-422b-91ae-364da2661108",
"shortName": "CVE"
},
"references": [
{
"tags": [
"x_transferred"
],
"url": "https://www.openeuler.org/en/security/safety-bulletin/detail.html?id=openEuler-SA-2022-1807"
},
{
"name": "FEDORA-2022-fe1a4e3cf0",
"tags": [
"vendor-advisory",
"x_transferred"
],
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5YSHZY753R7XW6CIKJVAWI373WW3YRRJ/"
},
{
"name": "FEDORA-2022-50e8a1b51d",
"tags": [
"vendor-advisory",
"x_transferred"
],
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OD4HEBSTI22FNYKOKK7W3X6ZQE6FV3XC/"
},
{
"name": "FEDORA-2022-44a20bba43",
"tags": [
"vendor-advisory",
"x_transferred"
],
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7Q26QDNOJDOFYWMJWEIK5XR62M2FF6IJ/"
},
{
"name": "FEDORA-2022-88772d0a2d",
"tags": [
"vendor-advisory",
"x_transferred"
],
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4S4PJRCJLEAWN2EKXGLSOBTL7O57V7NC/"
},
{
"name": "FEDORA-2022-ccc68b06cc",
"tags": [
"vendor-advisory",
"x_transferred"
],
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7WX5YE66CT7Y5C2HTHXSFDKQWYWYWJ2T/"
},
{
"url": "https://lists.debian.org/debian-lts-announce/2025/01/msg00026.html"
}
],
"title": "CVE Program Container"
}
],
"cna": {
"affected": [
{
"product": "libtar",
"vendor": "n/a",
"versions": [
{
"status": "affected",
"version": "\u003c1.2.21"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "The th_read() function doesn\u2019t free a variable t-\u003eth_buf.gnu_longlink after allocating memory, which may cause a memory leak."
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-401",
"description": "CWE-401: Missing Release of Memory after Effective Lifetime",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2022-12-28T00:00:00.000Z",
"orgId": "7e1ac599-2767-43fa-b3ea-f10178cc98f2",
"shortName": "openEuler"
},
"references": [
{
"url": "https://www.openeuler.org/en/security/safety-bulletin/detail.html?id=openEuler-SA-2022-1807"
},
{
"name": "FEDORA-2022-fe1a4e3cf0",
"tags": [
"vendor-advisory"
],
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5YSHZY753R7XW6CIKJVAWI373WW3YRRJ/"
},
{
"name": "FEDORA-2022-50e8a1b51d",
"tags": [
"vendor-advisory"
],
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OD4HEBSTI22FNYKOKK7W3X6ZQE6FV3XC/"
},
{
"name": "FEDORA-2022-44a20bba43",
"tags": [
"vendor-advisory"
],
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7Q26QDNOJDOFYWMJWEIK5XR62M2FF6IJ/"
},
{
"name": "FEDORA-2022-88772d0a2d",
"tags": [
"vendor-advisory"
],
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4S4PJRCJLEAWN2EKXGLSOBTL7O57V7NC/"
},
{
"name": "FEDORA-2022-ccc68b06cc",
"tags": [
"vendor-advisory"
],
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7WX5YE66CT7Y5C2HTHXSFDKQWYWYWJ2T/"
}
]
}
},
"cveMetadata": {
"assignerOrgId": "7e1ac599-2767-43fa-b3ea-f10178cc98f2",
"assignerShortName": "openEuler",
"cveId": "CVE-2021-33645",
"datePublished": "2022-08-09T00:00:00.000Z",
"dateReserved": "2021-05-28T00:00:00.000Z",
"dateUpdated": "2025-11-03T20:33:38.619Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2021-33645",
"date": "2026-09-21",
"epss": "0.01786",
"percentile": "0.77001"
},
"fkie_nvd": {
"configurations": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:a:feep:libtar:*:*:*:*:*:*:*:*",
"matchCriteriaId": "9FB33CE5-5B11-49D2-9277-67E941584A35",
"versionEndExcluding": "1.2.21",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
},
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:huawei:openeuler:20.03:sp1:*:*:lts:*:*:*",
"matchCriteriaId": "78AA9487-C85C-4F4F-9429-E0496080F7B5",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:huawei:openeuler:20.03:sp3:*:*:lts:*:*:*",
"matchCriteriaId": "2E9E5CF1-3FD7-413A-BD29-0EBA0E1E6766",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:huawei:openeuler:22.03:*:*:*:lts:*:*:*",
"matchCriteriaId": "435FECB5-9313-4400-A95F-8F7C9D5A0A07",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
},
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*",
"matchCriteriaId": "80E516C0-98A4-4ADE-B69F-66A772E2BAAA",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:*",
"matchCriteriaId": "5C675112-476C-4D7C-BCB9-A2FB2D0BC9FD",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:*",
"matchCriteriaId": "E30D0E6F-4AE8-4284-8716-991DFA48CC5D",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "The th_read() function doesn\u2019t free a variable t-\u003eth_buf.gnu_longlink after allocating memory, which may cause a memory leak."
},
{
"lang": "es",
"value": "La funci\u00f3n th_read() no libera una variable t-)th_buf.gnu_longlink despu\u00e9s de asignar memoria, lo que puede causar una p\u00e9rdida de memoria"
}
],
"id": "CVE-2021-33645",
"lastModified": "2024-11-21T06:09:16.087",
"metrics": {
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 7.5,
"baseSeverity": "HIGH",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"version": "3.1"
},
"exploitabilityScore": 3.9,
"impactScore": 3.6,
"source": "nvd@nist.gov",
"type": "Primary"
}
]
},
"published": "2022-08-10T20:15:20.573",
"references": [
{
"source": "securities@openeuler.org",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4S4PJRCJLEAWN2EKXGLSOBTL7O57V7NC/"
},
{
"source": "securities@openeuler.org",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5YSHZY753R7XW6CIKJVAWI373WW3YRRJ/"
},
{
"source": "securities@openeuler.org",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7Q26QDNOJDOFYWMJWEIK5XR62M2FF6IJ/"
},
{
"source": "securities@openeuler.org",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7WX5YE66CT7Y5C2HTHXSFDKQWYWYWJ2T/"
},
{
"source": "securities@openeuler.org",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OD4HEBSTI22FNYKOKK7W3X6ZQE6FV3XC/"
},
{
"source": "securities@openeuler.org",
"tags": [
"Third Party Advisory"
],
"url": "https://www.openeuler.org/en/security/safety-bulletin/detail.html?id=openEuler-SA-2022-1807"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4S4PJRCJLEAWN2EKXGLSOBTL7O57V7NC/"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5YSHZY753R7XW6CIKJVAWI373WW3YRRJ/"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7Q26QDNOJDOFYWMJWEIK5XR62M2FF6IJ/"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7WX5YE66CT7Y5C2HTHXSFDKQWYWYWJ2T/"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OD4HEBSTI22FNYKOKK7W3X6ZQE6FV3XC/"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Third Party Advisory"
],
"url": "https://www.openeuler.org/en/security/safety-bulletin/detail.html?id=openEuler-SA-2022-1807"
}
],
"sourceIdentifier": "securities@openeuler.org",
"vulnStatus": "Modified",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-401"
}
],
"source": "securities@openeuler.org",
"type": "Secondary"
},
{
"description": [
{
"lang": "en",
"value": "CWE-401"
}
],
"source": "nvd@nist.gov",
"type": "Primary"
}
]
},
"nvd": {
"cve": {
"configurations": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:a:feep:libtar:*:*:*:*:*:*:*:*",
"matchCriteriaId": "9FB33CE5-5B11-49D2-9277-67E941584A35",
"versionEndExcluding": "1.2.21",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
},
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:openatom:openeuler:20.03:sp1:*:*:lts:*:*:*",
"matchCriteriaId": "464D2E5A-0D36-4893-85A4-2267AE0333DE",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:openatom:openeuler:20.03:sp3:*:*:lts:*:*:*",
"matchCriteriaId": "A98D36A4-869D-4F90-9434-599915671828",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:openatom:openeuler:22.03:*:*:*:lts:*:*:*",
"matchCriteriaId": "5975B9D2-6A0F-43DE-806E-C8FC6D152EF6",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
},
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*",
"matchCriteriaId": "80E516C0-98A4-4ADE-B69F-66A772E2BAAA",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:*",
"matchCriteriaId": "5C675112-476C-4D7C-BCB9-A2FB2D0BC9FD",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:*",
"matchCriteriaId": "E30D0E6F-4AE8-4284-8716-991DFA48CC5D",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "The th_read() function doesn\u2019t free a variable t-\u003eth_buf.gnu_longlink after allocating memory, which may cause a memory leak."
},
{
"lang": "es",
"value": "La funci\u00f3n th_read() no libera una variable t-)th_buf.gnu_longlink despu\u00e9s de asignar memoria, lo que puede causar una p\u00e9rdida de memoria"
}
],
"id": "CVE-2021-33645",
"lastModified": "2025-11-03T21:15:41.387",
"metrics": {
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 7.5,
"baseSeverity": "HIGH",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"version": "3.1"
},
"exploitabilityScore": 3.9,
"impactScore": 3.6,
"source": "nvd@nist.gov",
"type": "Primary"
}
]
},
"published": "2022-08-10T20:15:20.573",
"references": [
{
"source": "securities@openeuler.org",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4S4PJRCJLEAWN2EKXGLSOBTL7O57V7NC/"
},
{
"source": "securities@openeuler.org",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5YSHZY753R7XW6CIKJVAWI373WW3YRRJ/"
},
{
"source": "securities@openeuler.org",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7Q26QDNOJDOFYWMJWEIK5XR62M2FF6IJ/"
},
{
"source": "securities@openeuler.org",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7WX5YE66CT7Y5C2HTHXSFDKQWYWYWJ2T/"
},
{
"source": "securities@openeuler.org",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OD4HEBSTI22FNYKOKK7W3X6ZQE6FV3XC/"
},
{
"source": "securities@openeuler.org",
"tags": [
"Third Party Advisory"
],
"url": "https://www.openeuler.org/en/security/safety-bulletin/detail.html?id=openEuler-SA-2022-1807"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"url": "https://lists.debian.org/debian-lts-announce/2025/01/msg00026.html"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4S4PJRCJLEAWN2EKXGLSOBTL7O57V7NC/"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5YSHZY753R7XW6CIKJVAWI373WW3YRRJ/"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7Q26QDNOJDOFYWMJWEIK5XR62M2FF6IJ/"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7WX5YE66CT7Y5C2HTHXSFDKQWYWYWJ2T/"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OD4HEBSTI22FNYKOKK7W3X6ZQE6FV3XC/"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Third Party Advisory"
],
"url": "https://www.openeuler.org/en/security/safety-bulletin/detail.html?id=openEuler-SA-2022-1807"
}
],
"sourceIdentifier": "securities@openeuler.org",
"vulnStatus": "Modified",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-401"
}
],
"source": "securities@openeuler.org",
"type": "Secondary"
},
{
"description": [
{
"lang": "en",
"value": "CWE-401"
}
],
"source": "nvd@nist.gov",
"type": "Primary"
}
]
}
},
"redhat_vex": {
"aggregate_severity": "Moderate",
"current_release_date": "2025-11-21T13:36:44+00:00",
"cve": "CVE-2021-33645",
"id": "CVE-2021-33645",
"initial_release_date": "2021-01-01T00:00:00+00:00",
"product_status:fixed": "16",
"product_status:known_affected": "5",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "libtar: memory leak found in th_read() function",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2021/cve-2021-33645.json",
"version": "3"
},
"suse_vex": {
"aggregate_severity": "important",
"current_release_date": "2026-06-25T03:20:03Z",
"cve": "CVE-2021-33645",
"id": "CVE-2021-33645",
"initial_release_date": "2024-06-04T12:57:03Z",
"product_status:recommended": "4",
"source": "SUSE CSAF VEX",
"status": "interim",
"title": "SUSE CVE CVE-2021-33645",
"url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2021-33645.json",
"version": "9"
}
}
}
Loading…
Loading…
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Loading…
The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Loading…
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
Loading…