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CVE-2026-52936

Estado: AnalizadaMedia (5.5)—

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.

CVSS

Probabilidad de explotación (EPSS)

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

Referencias

JSON original (NVD)

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  "id": "CVE-2026-52936",
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          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
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  "published": "2026-06-24T08:16:23.883",
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  "descriptions": [
    {
      "lang": "en",
      "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->jent_lock with a\nmutex so contended readers sleep instead of spinning on a shared lock\nheld across expensive entropy generation."
    }
  ],
  "lastModified": "2026-07-08T20:31:02.290",
  "configurations": [
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      "nodes": [
        {
          "negate": false,
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}