GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

GHSA-M8F2-RW7M-JRXF

Vulnerability from github – Published: 2026-01-14 15:33 – Updated: 2026-03-25 21:30
VLAI
Details

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

mm/slub: reset KASAN tag in defer_free() before accessing freed memory

When CONFIG_SLUB_TINY is enabled, kfree_nolock() calls kasan_slab_free() before defer_free(). On ARM64 with MTE (Memory Tagging Extension), kasan_slab_free() poisons the memory and changes the tag from the original (e.g., 0xf3) to a poison tag (0xfe).

When defer_free() then tries to write to the freed object to build the deferred free list via llist_add(), the pointer still has the old tag, causing a tag mismatch and triggering a KASAN use-after-free report:

BUG: KASAN: slab-use-after-free in defer_free+0x3c/0xbc mm/slub.c:6537 Write at addr f3f000000854f020 by task kworker/u8:6/983 Pointer tag: [f3], memory tag: [fe]

Fix this by calling kasan_reset_tag() before accessing the freed memory. This is safe because defer_free() is part of the allocator itself and is expected to manipulate freed memory for bookkeeping purposes.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2025-71110"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-416"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-01-14T15:16:00Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/slub: reset KASAN tag in defer_free() before accessing freed memory\n\nWhen CONFIG_SLUB_TINY is enabled, kfree_nolock() calls kasan_slab_free()\nbefore defer_free(). On ARM64 with MTE (Memory Tagging Extension),\nkasan_slab_free() poisons the memory and changes the tag from the\noriginal (e.g., 0xf3) to a poison tag (0xfe).\n\nWhen defer_free() then tries to write to the freed object to build the\ndeferred free list via llist_add(), the pointer still has the old tag,\ncausing a tag mismatch and triggering a KASAN use-after-free report:\n\n  BUG: KASAN: slab-use-after-free in defer_free+0x3c/0xbc mm/slub.c:6537\n  Write at addr f3f000000854f020 by task kworker/u8:6/983\n  Pointer tag: [f3], memory tag: [fe]\n\nFix this by calling kasan_reset_tag() before accessing the freed memory.\nThis is safe because defer_free() is part of the allocator itself and is\nexpected to manipulate freed memory for bookkeeping purposes.",
  "id": "GHSA-m8f2-rw7m-jrxf",
  "modified": "2026-03-25T21:30:22Z",
  "published": "2026-01-14T15:33:00Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-71110"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/53ca00a19d345197a37a1bf552e8d1e7b091666c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/65d4e5af2a2e82f4fc50d8259aee208fbc6b2c1d"
    }
  ],
  "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"
    }
  ]
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

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…

Detection rules are retrieved from Rulezet.

Loading…

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…