Vulnerability-Lookup

GHSA-WH23-V966-32JJ

Vulnerability from github – Published: 2025-03-07 09:30 – Updated: 2026-03-07 12:31

Details

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

io_uring/kbuf: reallocate buf lists on upgrade

IORING_REGISTER_PBUF_RING can reuse an old struct io_buffer_list if it was created for legacy selected buffer and has been emptied. It violates the requirement that most of the field should stay stable after publish. Always reallocate it instead.

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-2025-21836"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-03-07T09:15:16Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/kbuf: reallocate buf lists on upgrade\n\nIORING_REGISTER_PBUF_RING can reuse an old struct io_buffer_list if it\nwas created for legacy selected buffer and has been emptied. It violates\nthe requirement that most of the field should stay stable after publish.\nAlways reallocate it instead.",
  "id": "GHSA-wh23-v966-32jj",
  "modified": "2026-03-07T12:31:23Z",
  "published": "2025-03-07T09:30:35Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-21836"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/146a185f6c05ee263db715f860620606303c4633"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2a5febbef40ce968e295a7aeaa5d5cbd9e3e5ad4"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7d0dc28dae836caf7645fef62a10befc624dd17b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/8802766324e1f5d414a81ac43365c20142e85603"
    },
    {
      "type": "WEB",
      "url": "https://u1f383.github.io/slides/talks/2025_Hexacon-Deja_Vu_in_Linux_io_uring_Breaking_Memory_Sharing_Again_After_Generations_of_Fixes.pdf"
    }
  ],
  "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-2025-21836 (GCVE-0-2025-21836)

Vulnerability from cvelistv5 – Published: 2025-03-07 09:09 – Updated: 2026-10-15 21:51

Title

io_uring/kbuf: reallocate buf lists on upgrade

Summary

In the Linux kernel, the following vulnerability has been resolved: io_uring/kbuf: reallocate buf lists on upgrade IORING_REGISTER_PBUF_RING can reuse an old struct io_buffer_list if it was created for legacy selected buffer and has been emptied. It violates the requirement that most of the field should stay stable after publish. Always reallocate it instead.

Severity

7.8 (High)


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

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-10-15 21:43 UTC

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 6637 records in the last 180 days details

References

5 references

URL	Tags
https://git.kernel.org/stable/c/146a185f6c05ee263…
https://git.kernel.org/stable/c/7d0dc28dae836caf7…
https://git.kernel.org/stable/c/2a5febbef40ce968e…
https://git.kernel.org/stable/c/8802766324e1f5d41…
https://u1f383.github.io/slides/talks/2025_Hexaco…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 2fcabce2d7d34f69a888146dab15b36a917f09d4 , < 146a185f6c05ee263db715f860620606303c4633 (git) Affected: 2fcabce2d7d34f69a888146dab15b36a917f09d4 , < 7d0dc28dae836caf7645fef62a10befc624dd17b (git) Affected: 2fcabce2d7d34f69a888146dab15b36a917f09d4 , < 2a5febbef40ce968e295a7aeaa5d5cbd9e3e5ad4 (git) Affected: 2fcabce2d7d34f69a888146dab15b36a917f09d4 , < 8802766324e1f5d414a81ac43365c20142e85603 (git)
Linux	Linux	Affected: 5.19 Unaffected: 0 , < 5.19 (semver) Unaffected: 6.6.79 , ≤ 6.6.* (semver) Unaffected: 6.12.16 , ≤ 6.12.* (semver) Unaffected: 6.13.4 , ≤ 6.13.* (semver) Unaffected: 6.14 , ≤ * (original_commit_for_fix)

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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.

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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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