CVE-2021-47040 (GCVE-0-2021-47040)

Vulnerability from cvelistv5 – Published: 2024-02-28 08:13 – Updated: 2026-08-05 08:45
VLAI
Title
io_uring: fix overflows checks in provide buffers
Summary
In the Linux kernel, the following vulnerability has been resolved: io_uring: fix overflows checks in provide buffers Colin reported before possible overflow and sign extension problems in io_provide_buffers_prep(). As Linus pointed out previous attempt did nothing useful, see d81269fecb8ce ("io_uring: fix provide_buffers sign extension"). Do that with help of check_<op>_overflow helpers. And fix struct io_provide_buf::len type, as it doesn't make much sense to keep it signed.
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: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-09-10 15:57 UTC
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: efe68c1ca8f49e8c06afd74b699411bfbb8ba1ff , < cbbc13b115b8f18e0a714d89f87fbdc499acfe2d (git)
Affected: efe68c1ca8f49e8c06afd74b699411bfbb8ba1ff , < 51bf90901952aaac564bbdb36b2b503050c53dd9 (git)
Affected: efe68c1ca8f49e8c06afd74b699411bfbb8ba1ff , < 84b8c266c4bfe9ed5128e13253c388deb74b1b03 (git)
Affected: efe68c1ca8f49e8c06afd74b699411bfbb8ba1ff , < 38134ada0ceea3e848fe993263c0ff6207fd46e7 (git)
guessed Create a notification for this product.
Linux Linux Affected: 5.8
Unaffected: 0 , < 5.8 (semver)
Unaffected: 5.10.37 , ≤ 5.10.* (semver)
Unaffected: 5.11.21 , ≤ 5.11.* (semver)
Unaffected: 5.12.4 , ≤ 5.12.* (semver)
Unaffected: 5.13 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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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.
  • 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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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.