Vulnerability-Lookup

GHSA-X37V-HM75-XVF9

Vulnerability from github – Published: 2026-07-19 12:30 – Updated: 2026-07-20 15:31

Details

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

net/tcp-ao: fix use-after-free of key in del_async path

In tcp_ao_delete_key(), the del_async path skips the current_key and rnext_key validity checks present in the synchronous path, assuming these pointers are always NULL on LISTEN sockets. However, if a key was added with set_current=1/set_rnext=1 while the socket was in CLOSE state, current_key and rnext_key will be non-NULL after listen() transitions the socket to LISTEN.

When such a key is deleted with del_async=1, hlist_del_rcu() and call_rcu() free the key without clearing the dangling pointers. After the RCU grace period, getsockopt(TCP_AO_INFO) dereferences current_key->sndid and rnext_key->rcvid from freed slab memory.

Clear current_key and rnext_key in the del_async path when they reference the key being deleted.

Severity

7.8 (High)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-53389"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-19T12:16:49Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/tcp-ao: fix use-after-free of key in del_async path\n\nIn tcp_ao_delete_key(), the del_async path skips the current_key\nand rnext_key validity checks present in the synchronous path,\nassuming these pointers are always NULL on LISTEN sockets.  However,\nif a key was added with set_current=1/set_rnext=1 while the socket\nwas in CLOSE state, current_key and rnext_key will be non-NULL\nafter listen() transitions the socket to LISTEN.\n\nWhen such a key is deleted with del_async=1, hlist_del_rcu() and\ncall_rcu() free the key without clearing the dangling pointers.\nAfter the RCU grace period, getsockopt(TCP_AO_INFO) dereferences\ncurrent_key-\u003esndid and rnext_key-\u003ercvid from freed slab memory.\n\nClear current_key and rnext_key in the del_async path when they\nreference the key being deleted.",
  "id": "GHSA-x37v-hm75-xvf9",
  "modified": "2026-07-20T15:31:44Z",
  "published": "2026-07-19T12:30:22Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-53389"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5ba9950bc9078e19b69cca1e56d1553b125c6857"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6ce7ef41743740ce15c2061561b784148b565b3f"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7ddc29a094d96e9b3aa280433c6dc443df9eabf2"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e77fbefd1269b5c123e7c651a1ebdce1b87d19a0"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-53389 (GCVE-0-2026-53389)

Vulnerability from cvelistv5 – Published: 2026-07-19 12:01 – Updated: 2026-07-20 13:39

Title

net/tcp-ao: fix use-after-free of key in del_async path

Summary

In the Linux kernel, the following vulnerability has been resolved: net/tcp-ao: fix use-after-free of key in del_async path In tcp_ao_delete_key(), the del_async path skips the current_key and rnext_key validity checks present in the synchronous path, assuming these pointers are always NULL on LISTEN sockets. However, if a key was added with set_current=1/set_rnext=1 while the socket was in CLOSE state, current_key and rnext_key will be non-NULL after listen() transitions the socket to LISTEN. When such a key is deleted with del_async=1, hlist_del_rcu() and call_rcu() free the key without clearing the dangling pointers. After the RCU grace period, getsockopt(TCP_AO_INFO) dereferences current_key->sndid and rnext_key->rcvid from freed slab memory. Clear current_key and rnext_key in the del_async path when they reference the key being deleted.

Severity

7.8 (High)


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

Assigner

Linux

References

4 references

URL	Tags
https://git.kernel.org/stable/c/6ce7ef41743740ce1…
https://git.kernel.org/stable/c/e77fbefd1269b5c12…
https://git.kernel.org/stable/c/7ddc29a094d96e9b3…
https://git.kernel.org/stable/c/5ba9950bc9078e19b…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: d6732b95b6fbbc6d5bb9d2f809e275763640c4a2 , < 6ce7ef41743740ce15c2061561b784148b565b3f (git) Affected: d6732b95b6fbbc6d5bb9d2f809e275763640c4a2 , < e77fbefd1269b5c123e7c651a1ebdce1b87d19a0 (git) Affected: d6732b95b6fbbc6d5bb9d2f809e275763640c4a2 , < 7ddc29a094d96e9b3aa280433c6dc443df9eabf2 (git) Affected: d6732b95b6fbbc6d5bb9d2f809e275763640c4a2 , < 5ba9950bc9078e19b69cca1e56d1553b125c6857 (git)
Linux	Linux	Affected: 6.7 Unaffected: 0 , < 6.7 (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)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/ipv4/tcp_ao.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
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              "status": "affected",
              "version": "d6732b95b6fbbc6d5bb9d2f809e275763640c4a2",
              "versionType": "git"
            },
            {
              "lessThan": "e77fbefd1269b5c123e7c651a1ebdce1b87d19a0",
              "status": "affected",
              "version": "d6732b95b6fbbc6d5bb9d2f809e275763640c4a2",
              "versionType": "git"
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              "lessThan": "7ddc29a094d96e9b3aa280433c6dc443df9eabf2",
              "status": "affected",
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              "versionType": "git"
            },
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              "lessThan": "5ba9950bc9078e19b69cca1e56d1553b125c6857",
              "status": "affected",
              "version": "d6732b95b6fbbc6d5bb9d2f809e275763640c4a2",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/ipv4/tcp_ao.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.7"
            },
            {
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              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
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              "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"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.95",
                  "versionStartIncluding": "6.7",
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                },
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        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
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        "dateUpdated": "2026-07-20T13:39:52.858Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
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        },
        {
          "url": "https://git.kernel.org/stable/c/5ba9950bc9078e19b69cca1e56d1553b125c6857"
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    "assignerShortName": "Linux",
    "cveId": "CVE-2026-53389",
    "datePublished": "2026-07-19T12:01:54.386Z",
    "dateReserved": "2026-06-09T07:44:35.402Z",
    "dateUpdated": "2026-07-20T13:39:52.858Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
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}

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

GHSA-X37V-HM75-XVF9

CVE-2026-53389 (GCVE-0-2026-53389)

Tags

Sightings

Nomenclature