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CVE-2026-43366 (GCVE-0-2026-43366)

Vulnerability from cvelistv5 – Published: 2026-05-08 14:21 – Updated: 2026-08-05 12:27
VLAI
Title
io_uring/kbuf: check if target buffer list is still legacy on recycle
Summary
In the Linux kernel, the following vulnerability has been resolved: io_uring/kbuf: check if target buffer list is still legacy on recycle There's a gap between when the buffer was grabbed and when it potentially gets recycled, where if the list is empty, someone could've upgraded it to a ring provided type. This can happen if the request is forced via io-wq. The legacy recycling is missing checking if the buffer_list still exists, and if it's of the correct type. Add those checks.
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 CPE status
Linux Linux Affected: c7fb19428d67dd0a2a78a4f237af01d39c78dc5a , < a7b33671e418fca507feebd1d56e7f4952a4b25c (git)
Affected: c7fb19428d67dd0a2a78a4f237af01d39c78dc5a , < 439a6728ec4641ffad1ca796622c19bc525e570f (git)
Affected: c7fb19428d67dd0a2a78a4f237af01d39c78dc5a , < f3fb54e7a8b4aadcc2836ee463eec8c88709b8aa (git)
Affected: c7fb19428d67dd0a2a78a4f237af01d39c78dc5a , < 50ad880db3013c6fee0ef13781762a39e2e7ef83 (git)
Affected: c7fb19428d67dd0a2a78a4f237af01d39c78dc5a , < 97b57f69fee1b61b41acbf37e7720cac9d389fa4 (git)
Affected: c7fb19428d67dd0a2a78a4f237af01d39c78dc5a , < c2c185be5c85d37215397c8e8781abf0a69bec1f (git)
guessed Create a notification for this product.
Linux Linux Affected: 5.19
Unaffected: 0 , < 5.19 (semver)
Unaffected: 6.1.167 , ≤ 6.1.* (semver)
Unaffected: 6.6.130 , ≤ 6.6.* (semver)
Unaffected: 6.12.78 , ≤ 6.12.* (semver)
Unaffected: 6.18.19 , ≤ 6.18.* (semver)
Unaffected: 6.19.9 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-07-02T12:46:36+00:00",
      "cve": "CVE-2026-43366",
      "id": "CVE-2026-43366",
      "initial_release_date": "2026-05-08T00:00:00+00:00",
      "product_status:known_affected": "184",
      "product_status:known_not_affected": "90",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: io_uring/kbuf: check if target buffer list is still legacy on recycle",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43366.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-09-11T01:18:12Z",
      "cve": "CVE-2026-43366",
      "id": "CVE-2026-43366",
      "initial_release_date": "2026-05-13T03:34:50Z",
      "product_status:first_fixed": "2",
      "product_status:known_affected": "394",
      "product_status:known_not_affected": "221",
      "product_status:recommended": "540",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-43366",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-43366.json",
      "version": "35"
    }
  }
}



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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

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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.
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  • 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.