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
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
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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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: jitterentropy - replace long-held spinlock with mutex\n\njent_kcapi_random() serializes the shared jitterentropy state, but it\ncurrently holds a spinlock across the jent_read_entropy() call. That\npath performs expensive jitter collection and SHA3 conditioning, so\nparallel readers can trigger stalls as contending waiters spin for\nthe same lock.\n\nTo prevent non-preemptible lock hold, replace rng-\u003ejent_lock with a\nmutex so contended readers sleep instead of spinning on a shared lock\nheld across expensive entropy generation."
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        "shortName": "Linux"
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    "datePublished": "2026-06-24T07:14:26.649Z",
    "dateReserved": "2026-06-09T07:44:35.370Z",
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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.
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  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
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  • 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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