CVE-2026-52936 (GCVE-0-2026-52936)

Vulnerability from cvelistv5 – Published: 2026-06-24 07:14 – Updated: 2026-06-24 07:14
VLAI
Title
crypto: jitterentropy - replace long-held spinlock with mutex
Summary
In the Linux kernel, the following vulnerability has been resolved: crypto: jitterentropy - replace long-held spinlock with mutex jent_kcapi_random() serializes the shared jitterentropy state, but it currently holds a spinlock across the jent_read_entropy() call. That path performs expensive jitter collection and SHA3 conditioning, so parallel readers can trigger stalls as contending waiters spin for the same lock. To prevent non-preemptible lock hold, replace rng->jent_lock with a mutex so contended readers sleep instead of spinning on a shared lock held across expensive entropy generation.
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: bb5530e4082446aac3a3d69780cd4dbfa4520013 , < 18216b8ab6904753eaf31baf453cb02ecd202ba4 (git)
Affected: bb5530e4082446aac3a3d69780cd4dbfa4520013 , < 4c03e6eb98443dc4d6d422a9780034a5b75376b4 (git)
Affected: bb5530e4082446aac3a3d69780cd4dbfa4520013 , < ff734dbd9e2432601a6dcd167cfb0bf8a36d1880 (git)
Affected: bb5530e4082446aac3a3d69780cd4dbfa4520013 , < ec427dc5286da1ed08f2d510e2147a7581b0cb02 (git)
Affected: bb5530e4082446aac3a3d69780cd4dbfa4520013 , < 01d798e9feb30212952d4e992801ba6bd6a82351 (git)
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Linux Linux Affected: 4.2
Unaffected: 0 , < 4.2 (semver)
Unaffected: 6.6.141 , ≤ 6.6.* (semver)
Unaffected: 6.12.91 , ≤ 6.12.* (semver)
Unaffected: 6.18.33 , ≤ 6.18.* (semver)
Unaffected: 7.0.10 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (original_commit_for_fix)
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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.


Detection rules are retrieved from Rulezet.


Related by attack behaviour

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.