CVE-2026-43109 (GCVE-0-2026-43109)

Vulnerability from cvelistv5 – Published: 2026-05-06 07:40 – Updated: 2026-05-17 15:21
VLAI
Title
x86: shadow stacks: proper error handling for mmap lock
Summary
In the Linux kernel, the following vulnerability has been resolved: x86: shadow stacks: proper error handling for mmap lock 김영민 reports that shstk_pop_sigframe() doesn't check for errors from mmap_read_lock_killable(), which is a silly oversight, and also shows that we haven't marked those functions with "__must_check", which would have immediately caught it. So let's fix both issues.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 7fad2a432cd35bbf104d2d9d426e74902f22aa95 , < c79cf42321600e931933e11f94aba8b245d4cd66 (git)
Affected: 7fad2a432cd35bbf104d2d9d426e74902f22aa95 , < 1a30468eff661937d978495644d2e5ebfeef5ce6 (git)
Affected: 7fad2a432cd35bbf104d2d9d426e74902f22aa95 , < c64cebcc5c4f223dbcbe7dcdf74908fc092a0aa4 (git)
Affected: 7fad2a432cd35bbf104d2d9d426e74902f22aa95 , < 262b6d38a81d51b135db81e1f30c13d30e38feee (git)
Affected: 7fad2a432cd35bbf104d2d9d426e74902f22aa95 , < 52f657e34d7b21b47434d9d8b26fa7f6778b63a0 (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.6
Unaffected: 0 , < 6.6 (semver)
Unaffected: 6.6.140 , ≤ 6.6.* (semver)
Unaffected: 6.12.88 , ≤ 6.12.* (semver)
Unaffected: 6.18.24 , ≤ 6.18.* (semver)
Unaffected: 6.19.14 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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}



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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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