Vulnerability-Lookup

GHSA-8H74-QH3G-94FX

Vulnerability from github – Published: 2026-05-27 15:33 – Updated: 2026-06-25 21:31

Details

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

apparmor: avoid per-cpu hold underflow in aa_get_buffer

When aa_get_buffer() pulls from the per-cpu list it unconditionally decrements cache->hold. If hold reaches 0 while count is still non-zero, the unsigned decrement wraps to UINT_MAX. This keeps hold non-zero for a very long time, so aa_put_buffer() never returns buffers to the global list, which can starve other CPUs and force repeated kmalloc(aa_g_path_max) allocations.

Guard the decrement so hold never underflows.

Severity

5.5 (Medium)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-45884"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-191"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-27T14:17:02Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\napparmor: avoid per-cpu hold underflow in aa_get_buffer\n\nWhen aa_get_buffer() pulls from the per-cpu list it unconditionally\ndecrements cache-\u003ehold. If hold reaches 0 while count is still non-zero,\nthe unsigned decrement wraps to UINT_MAX. This keeps hold non-zero for a\nvery long time, so aa_put_buffer() never returns buffers to the global\nlist, which can starve other CPUs and force repeated kmalloc(aa_g_path_max)\nallocations.\n\nGuard the decrement so hold never underflows.",
  "id": "GHSA-8h74-qh3g-94fx",
  "modified": "2026-06-25T21:31:20Z",
  "published": "2026-05-27T15:33:14Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-45884"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/202824a1f89a9786c20a3d646a7c88d223abb1b2"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4bcddd0f6b2e52b4c7b520e4d36a115caf5b7169"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/640cf2f09575c9dc344b3f7be2498d31e3923ead"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/80c334acc6d0bee8605a358a33e69b4aea1ffb92"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-45884 (GCVE-0-2026-45884)

Vulnerability from cvelistv5 – Published: 2026-05-27 12:16 – Updated: 2026-05-27 12:16

Title

apparmor: avoid per-cpu hold underflow in aa_get_buffer

Summary

In the Linux kernel, the following vulnerability has been resolved: apparmor: avoid per-cpu hold underflow in aa_get_buffer When aa_get_buffer() pulls from the per-cpu list it unconditionally decrements cache->hold. If hold reaches 0 while count is still non-zero, the unsigned decrement wraps to UINT_MAX. This keeps hold non-zero for a very long time, so aa_put_buffer() never returns buffers to the global list, which can starve other CPUs and force repeated kmalloc(aa_g_path_max) allocations. Guard the decrement so hold never underflows.

Severity

No CVSS data available.

Assigner

Linux mitre root

References

4 references

URL	Tags
https://git.kernel.org/stable/c/202824a1f89a9786c…
https://git.kernel.org/stable/c/80c334acc6d0bee86…
https://git.kernel.org/stable/c/4bcddd0f6b2e52b4c…
https://git.kernel.org/stable/c/640cf2f09575c9dc3…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: ea9bae12d02819556db63348db8bd8441eb316f2 , < 202824a1f89a9786c20a3d646a7c88d223abb1b2 (git) Affected: ea9bae12d02819556db63348db8bd8441eb316f2 , < 80c334acc6d0bee8605a358a33e69b4aea1ffb92 (git) Affected: ea9bae12d02819556db63348db8bd8441eb316f2 , < 4bcddd0f6b2e52b4c7b520e4d36a115caf5b7169 (git) Affected: ea9bae12d02819556db63348db8bd8441eb316f2 , < 640cf2f09575c9dc344b3f7be2498d31e3923ead (git)
Linux	Linux	Affected: 6.7 Unaffected: 0 , < 6.7 (semver) Unaffected: 6.12.75 , ≤ 6.12.* (semver) Unaffected: 6.18.14 , ≤ 6.18.* (semver) Unaffected: 6.19.4 , ≤ 6.19.* (semver) Unaffected: 7.0 , ≤ * (original_commit_for_fix)

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JSON

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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.

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