CVE-2026-31554 (GCVE-0-2026-31554)

Vulnerability from cvelistv5 – Published: 2026-04-24 14:35 – Updated: 2026-08-05 12:23
VLAI
Title
futex: Require sys_futex_requeue() to have identical flags
Summary
In the Linux kernel, the following vulnerability has been resolved: futex: Require sys_futex_requeue() to have identical flags Nicholas reported that his LLM found it was possible to create a UaF when sys_futex_requeue() is used with different flags. The initial motivation for allowing different flags was the variable sized futex, but since that hasn't been merged (yet), simply mandate the flags are identical, as is the case for the old style sys_futex() requeue operations.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 0f4b5f972216782a4acb1ae00dcb55173847c2ff , < 027145ace09fad4c7cbcd6c61fe9b429c63eb0e5 (git)
Affected: 0f4b5f972216782a4acb1ae00dcb55173847c2ff , < 18b7d09c2b794c71d4252f3ea2cf84ad12b73d6a (git)
Affected: 0f4b5f972216782a4acb1ae00dcb55173847c2ff , < e2f78c7ec1655fedd945366151ba54fcb9580508 (git)
Affected: 0f4b5f972216782a4acb1ae00dcb55173847c2ff , < 19f94b39058681dec64a10ebeb6f23fe7fc3f77a (git)
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Linux Linux Affected: 6.7
Unaffected: 0 , < 6.7 (semver)
Unaffected: 6.12.80 , ≤ 6.12.* (semver)
Unaffected: 6.18.21 , ≤ 6.18.* (semver)
Unaffected: 6.19.11 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
Create a notification for this product.
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{
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          "programFiles": [
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    "dateReserved": "2026-03-09T15:48:24.115Z",
    "dateUpdated": "2026-08-05T12:23:28.646Z",
    "state": "PUBLISHED"
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    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-07-09T07:53:29+00:00",
      "cve": "CVE-2026-31554",
      "id": "CVE-2026-31554",
      "initial_release_date": "2026-04-24T00:00:00+00:00",
      "product_status:known_affected": "184",
      "product_status:known_not_affected": "90",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: futex: Require sys_futex_requeue() to have identical flags",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-31554.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-08-07T00:08:56Z",
      "cve": "CVE-2026-31554",
      "id": "CVE-2026-31554",
      "initial_release_date": "2026-04-25T01:39:36Z",
      "product_status:first_fixed": "2",
      "product_status:known_affected": "394",
      "product_status:known_not_affected": "300",
      "product_status:recommended": "220",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-31554",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-31554.json",
      "version": "9"
    }
  }
}



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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.


Detection rules are retrieved from Rulezet.