Vulnerability-Lookup

CVE-2026-63828 (GCVE-0-2026-63828)

Vulnerability from cvelistv5 – Published: 2026-07-19 12:02 – Updated: 2026-07-20 13:40

Title

apparmor: mediate the implicit connect of TCP fast open sendmsg

Summary

In the Linux kernel, the following vulnerability has been resolved: apparmor: mediate the implicit connect of TCP fast open sendmsg sendmsg()/sendto() with MSG_FASTOPEN is a combination of connect(2) and write(2): it opens the connection in the SYN. apparmor_socket_sendmsg() only checks AA_MAY_SEND, so a profile that grants send but denies connect lets a confined task open an outbound TCP/MPTCP connection that connect(2) would have refused, bypassing connect mediation. Mediate the implicit connect when MSG_FASTOPEN is set and a destination is supplied. Add it to apparmor_socket_sendmsg() (not the shared aa_sock_msg_perm() helper, which recvmsg also uses) and call aa_sk_perm() directly, mirroring the selinux and tomoyo fixes. sk_is_tcp() does not cover MPTCP fast open, so the SOCK_STREAM/IPPROTO_MPTCP arm is explicit.

Severity

8.4 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N

Assigner

Linux

References

6 references

URL	Tags
https://git.kernel.org/stable/c/7f57428ce00891d26…
https://git.kernel.org/stable/c/faea60deaa05c76f0…
https://git.kernel.org/stable/c/07b71c342382b854a…
https://git.kernel.org/stable/c/4a69b83045d3195d5…
https://git.kernel.org/stable/c/45ebb934ea50b436c…
https://git.kernel.org/stable/c/4d587cd8a72155089…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: cf60af03ca4e71134206809ea892e49b92a88896 , < 7f57428ce00891d26b0f087ef754a4d820ec83aa (git) Affected: cf60af03ca4e71134206809ea892e49b92a88896 , < faea60deaa05c76f0772650f42eafde12bd39d93 (git) Affected: cf60af03ca4e71134206809ea892e49b92a88896 , < 07b71c342382b854ab8030b244aeab6a7228ad7d (git) Affected: cf60af03ca4e71134206809ea892e49b92a88896 , < 4a69b83045d3195d5b9a9b053ad840ddb2998b4e (git) Affected: cf60af03ca4e71134206809ea892e49b92a88896 , < 45ebb934ea50b436ce49b2f159f090dab0d7fa28 (git) Affected: cf60af03ca4e71134206809ea892e49b92a88896 , < 4d587cd8a72155089a627130bbd4716ec0856e21 (git)
Linux	Linux	Affected: 3.6 Unaffected: 0 , < 3.6 (semver) Unaffected: 6.1.177 , ≤ 6.1.* (semver) Unaffected: 6.6.144 , ≤ 6.6.* (semver) Unaffected: 6.12.95 , ≤ 6.12.* (semver) Unaffected: 6.18.38 , ≤ 6.18.* (semver) Unaffected: 7.1.3 , ≤ 7.1.* (semver) Unaffected: 7.2-rc1 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
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          "programFiles": [
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              "status": "unaffected",
              "version": "6.12.95",
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            {
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              "status": "unaffected",
              "version": "6.18.38",
              "versionType": "semver"
            },
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              "status": "unaffected",
              "version": "7.1.3",
              "versionType": "semver"
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              "status": "unaffected",
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          ]
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                  "vulnerable": true
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        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 8.4,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N",
            "version": "3.1"
          }
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    "datePublished": "2026-07-19T12:02:22.644Z",
    "dateReserved": "2026-07-19T07:54:57.014Z",
    "dateUpdated": "2026-07-20T13:40:31.639Z",
    "state": "PUBLISHED"
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      "date": "2026-07-20",
      "epss": "0.00169",
      "percentile": "0.06602"
    },
    "microsoft_vex": {
      "current_release_date": "2026-07-20T01:07:39.000Z",
      "cve": "CVE-2026-63828",
      "id": "msrc_CVE-2026-63828",
      "initial_release_date": "2026-07-20T01:07:39.000Z",
      "product_status:under_investigation": "1",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "apparmor: mediate the implicit connect of TCP fast open sendmsg",
      "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-63828.json",
      "version": "1"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-63828\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-07-19T12:16:56.110\",\"lastModified\":\"2026-07-19T12:16:56.110\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\napparmor: mediate the implicit connect of TCP fast open sendmsg\\n\\nsendmsg()/sendto() with MSG_FASTOPEN is a combination of connect(2) and\\nwrite(2): it opens the connection in the SYN. apparmor_socket_sendmsg()\\nonly checks AA_MAY_SEND, so a profile that grants send but denies connect\\nlets a confined task open an outbound TCP/MPTCP connection that connect(2)\\nwould have refused, bypassing connect mediation.\\n\\nMediate the implicit connect when MSG_FASTOPEN is set and a destination\\nis supplied. Add it to apparmor_socket_sendmsg() (not the shared\\naa_sock_msg_perm() helper, which recvmsg also uses) and call aa_sk_perm()\\ndirectly, mirroring the selinux and tomoyo fixes. sk_is_tcp() does not\\ncover MPTCP fast open, so the SOCK_STREAM/IPPROTO_MPTCP arm is explicit.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"security/apparmor/lsm.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"cf60af03ca4e71134206809ea892e49b92a88896\",\"lessThan\":\"7f57428ce00891d26b0f087ef754a4d820ec83aa\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"cf60af03ca4e71134206809ea892e49b92a88896\",\"lessThan\":\"faea60deaa05c76f0772650f42eafde12bd39d93\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"cf60af03ca4e71134206809ea892e49b92a88896\",\"lessThan\":\"07b71c342382b854ab8030b244aeab6a7228ad7d\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"cf60af03ca4e71134206809ea892e49b92a88896\",\"lessThan\":\"4a69b83045d3195d5b9a9b053ad840ddb2998b4e\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"cf60af03ca4e71134206809ea892e49b92a88896\",\"lessThan\":\"45ebb934ea50b436ce49b2f159f090dab0d7fa28\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"cf60af03ca4e71134206809ea892e49b92a88896\",\"lessThan\":\"4d587cd8a72155089a627130bbd4716ec0856e21\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"security/apparmor/lsm.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"3.6\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"3.6\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.177\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.144\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.95\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.38\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.1.3\",\"lessThanOrEqual\":\"7.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.2-rc1\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/07b71c342382b854ab8030b244aeab6a7228ad7d\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/45ebb934ea50b436ce49b2f159f090dab0d7fa28\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/4a69b83045d3195d5b9a9b053ad840ddb2998b4e\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/4d587cd8a72155089a627130bbd4716ec0856e21\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/7f57428ce00891d26b0f087ef754a4d820ec83aa\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/faea60deaa05c76f0772650f42eafde12bd39d93\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "suse_vex": {
      "aggregate_severity": "not set",
      "current_release_date": "2026-07-19T17:34:36Z",
      "cve": "CVE-2026-63828",
      "id": "CVE-2026-63828",
      "initial_release_date": "2026-07-19T17:34:36Z",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-63828",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-63828.json",
      "version": "2"
    }
  }
}

FKIE_CVE-2026-63828

Vulnerability from fkie_nvd - Published: 2026-07-19 12:16 - Updated: 2026-07-19 12:16

Severity

Summary

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/07b71c342382b854ab8030b244aeab6a7228ad7d
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/45ebb934ea50b436ce49b2f159f090dab0d7fa28
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/4a69b83045d3195d5b9a9b053ad840ddb2998b4e
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/4d587cd8a72155089a627130bbd4716ec0856e21
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/7f57428ce00891d26b0f087ef754a4d820ec83aa
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/faea60deaa05c76f0772650f42eafde12bd39d93

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "security/apparmor/lsm.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "7f57428ce00891d26b0f087ef754a4d820ec83aa",
              "status": "affected",
              "version": "cf60af03ca4e71134206809ea892e49b92a88896",
              "versionType": "git"
            },
            {
              "lessThan": "faea60deaa05c76f0772650f42eafde12bd39d93",
              "status": "affected",
              "version": "cf60af03ca4e71134206809ea892e49b92a88896",
              "versionType": "git"
            },
            {
              "lessThan": "07b71c342382b854ab8030b244aeab6a7228ad7d",
              "status": "affected",
              "version": "cf60af03ca4e71134206809ea892e49b92a88896",
              "versionType": "git"
            },
            {
              "lessThan": "4a69b83045d3195d5b9a9b053ad840ddb2998b4e",
              "status": "affected",
              "version": "cf60af03ca4e71134206809ea892e49b92a88896",
              "versionType": "git"
            },
            {
              "lessThan": "45ebb934ea50b436ce49b2f159f090dab0d7fa28",
              "status": "affected",
              "version": "cf60af03ca4e71134206809ea892e49b92a88896",
              "versionType": "git"
            },
            {
              "lessThan": "4d587cd8a72155089a627130bbd4716ec0856e21",
              "status": "affected",
              "version": "cf60af03ca4e71134206809ea892e49b92a88896",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "security/apparmor/lsm.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "3.6"
            },
            {
              "lessThan": "3.6",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.177",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.144",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.95",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.38",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.3",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2-rc1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\napparmor: mediate the implicit connect of TCP fast open sendmsg\n\nsendmsg()/sendto() with MSG_FASTOPEN is a combination of connect(2) and\nwrite(2): it opens the connection in the SYN. apparmor_socket_sendmsg()\nonly checks AA_MAY_SEND, so a profile that grants send but denies connect\nlets a confined task open an outbound TCP/MPTCP connection that connect(2)\nwould have refused, bypassing connect mediation.\n\nMediate the implicit connect when MSG_FASTOPEN is set and a destination\nis supplied. Add it to apparmor_socket_sendmsg() (not the shared\naa_sock_msg_perm() helper, which recvmsg also uses) and call aa_sk_perm()\ndirectly, mirroring the selinux and tomoyo fixes. sk_is_tcp() does not\ncover MPTCP fast open, so the SOCK_STREAM/IPPROTO_MPTCP arm is explicit."
    }
  ],
  "id": "CVE-2026-63828",
  "lastModified": "2026-07-19T12:16:56.110",
  "metrics": {},
  "published": "2026-07-19T12:16:56.110",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/07b71c342382b854ab8030b244aeab6a7228ad7d"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/45ebb934ea50b436ce49b2f159f090dab0d7fa28"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/4a69b83045d3195d5b9a9b053ad840ddb2998b4e"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/4d587cd8a72155089a627130bbd4716ec0856e21"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/7f57428ce00891d26b0f087ef754a4d820ec83aa"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/faea60deaa05c76f0772650f42eafde12bd39d93"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}

GHSA-FVHV-V8P3-VRWQ

Vulnerability from github – Published: 2026-07-19 12:30 – Updated: 2026-07-19 12:30

Details

In the Linux kernel, the following vulnerability has been resolved:

apparmor: mediate the implicit connect of TCP fast open sendmsg

sendmsg()/sendto() with MSG_FASTOPEN is a combination of connect(2) and write(2): it opens the connection in the SYN. apparmor_socket_sendmsg() only checks AA_MAY_SEND, so a profile that grants send but denies connect lets a confined task open an outbound TCP/MPTCP connection that connect(2) would have refused, bypassing connect mediation.

Mediate the implicit connect when MSG_FASTOPEN is set and a destination is supplied. Add it to apparmor_socket_sendmsg() (not the shared aa_sock_msg_perm() helper, which recvmsg also uses) and call aa_sk_perm() directly, mirroring the selinux and tomoyo fixes. sk_is_tcp() does not cover MPTCP fast open, so the SOCK_STREAM/IPPROTO_MPTCP arm is explicit.

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-63828"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-19T12:16:56Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\napparmor: mediate the implicit connect of TCP fast open sendmsg\n\nsendmsg()/sendto() with MSG_FASTOPEN is a combination of connect(2) and\nwrite(2): it opens the connection in the SYN. apparmor_socket_sendmsg()\nonly checks AA_MAY_SEND, so a profile that grants send but denies connect\nlets a confined task open an outbound TCP/MPTCP connection that connect(2)\nwould have refused, bypassing connect mediation.\n\nMediate the implicit connect when MSG_FASTOPEN is set and a destination\nis supplied. Add it to apparmor_socket_sendmsg() (not the shared\naa_sock_msg_perm() helper, which recvmsg also uses) and call aa_sk_perm()\ndirectly, mirroring the selinux and tomoyo fixes. sk_is_tcp() does not\ncover MPTCP fast open, so the SOCK_STREAM/IPPROTO_MPTCP arm is explicit.",
  "id": "GHSA-fvhv-v8p3-vrwq",
  "modified": "2026-07-19T12:30:24Z",
  "published": "2026-07-19T12:30:24Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-63828"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/07b71c342382b854ab8030b244aeab6a7228ad7d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/45ebb934ea50b436ce49b2f159f090dab0d7fa28"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4a69b83045d3195d5b9a9b053ad840ddb2998b4e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4d587cd8a72155089a627130bbd4716ec0856e21"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7f57428ce00891d26b0f087ef754a4d820ec83aa"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/faea60deaa05c76f0772650f42eafde12bd39d93"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

MSRC_CVE-2026-63828

Vulnerability from csaf_microsoft - Published: 2026-07-20 01:07 - Updated: 2026-07-20 01:07

Summary

apparmor: mediate the implicit connect of TCP fast open sendmsg

Notes

Additional Resources: To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle

Disclaimer: The information provided in the Microsoft Knowledge Base is provided \"as is\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.

CVE-2026-63828

Affected products

Under investigation 1 product

Product	Identifier	Version	Remediation
Unresolved product id: 17084-1		—

References

4 references

URL	Category
https://msrc.microsoft.com/csaf/vex/2026/msrc_cve…	self
https://support.microsoft.com/lifecycle	external
https://www.first.org/cvss	external
https://msrc.microsoft.com/csaf/vex/2026/msrc_cve…	self

JSON

To clipboard

{
  "document": {
    "category": "csaf_vex",
    "csaf_version": "2.0",
    "distribution": {
      "text": "Public",
      "tlp": {
        "label": "WHITE",
        "url": "https://www.first.org/tlp/"
      }
    },
    "lang": "en-US",
    "notes": [
      {
        "category": "general",
        "text": "To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle",
        "title": "Additional Resources"
      },
      {
        "category": "legal_disclaimer",
        "text": "The information provided in the Microsoft Knowledge Base is provided \\\"as is\\\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.",
        "title": "Disclaimer"
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "secure@microsoft.com",
      "name": "Microsoft Security Response Center",
      "namespace": "https://msrc.microsoft.com"
    },
    "references": [
      {
        "category": "self",
        "summary": "CVE-2026-63828 apparmor: mediate the implicit connect of TCP fast open sendmsg - VEX",
        "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-63828.json"
      },
      {
        "category": "external",
        "summary": "Microsoft Support Lifecycle",
        "url": "https://support.microsoft.com/lifecycle"
      },
      {
        "category": "external",
        "summary": "Common Vulnerability Scoring System",
        "url": "https://www.first.org/cvss"
      }
    ],
    "title": "apparmor: mediate the implicit connect of TCP fast open sendmsg",
    "tracking": {
      "current_release_date": "2026-07-20T01:07:39.000Z",
      "generator": {
        "date": "2026-07-20T07:05:32.472Z",
        "engine": {
          "name": "MSRC Generator",
          "version": "1.0"
        }
      },
      "id": "msrc_CVE-2026-63828",
      "initial_release_date": "2026-07-20T01:07:39.000Z",
      "revision_history": [
        {
          "date": "2026-07-20T01:07:39.000Z",
          "legacy_version": "1",
          "number": "1",
          "summary": "Information published."
        }
      ],
      "status": "final",
      "version": "1"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version",
                "name": "3.0",
                "product": {
                  "name": "Azure Linux 3.0",
                  "product_id": "17084"
                }
              }
            ],
            "category": "product_name",
            "name": "Azure Linux"
          },
          {
            "category": "product_name",
            "name": "azl3 kernel 0:6.6.143.1-1.azl3",
            "product": {
              "name": "azl3 kernel 0:6.6.143.1-1.azl3",
              "product_id": "1"
            }
          }
        ],
        "category": "vendor",
        "name": "Microsoft"
      }
    ],
    "relationships": [
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "azl3 kernel 0:6.6.143.1-1.azl3 as a component of Azure Linux 3.0",
          "product_id": "17084-1"
        },
        "product_reference": "1",
        "relates_to_product_reference": "17084"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-63828",
      "notes": [
        {
          "category": "general",
          "text": "Linux",
          "title": "Assigning CNA"
        }
      ],
      "product_status": {
        "under_investigation": [
          "17084-1"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "CVE-2026-63828 apparmor: mediate the implicit connect of TCP fast open sendmsg - VEX",
          "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-63828.json"
        }
      ],
      "title": "apparmor: mediate the implicit connect of TCP fast open sendmsg"
    }
  ]
}

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.

Detection rules are retrieved from Rulezet.

Action not permitted

CVE-2026-63828 (GCVE-0-2026-63828)

FKIE_CVE-2026-63828

GHSA-FVHV-V8P3-VRWQ

MSRC_CVE-2026-63828

Tags

Sightings

Nomenclature