CVE-2026-52936

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 v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/01d798e9feb30212952d4e992801ba6bd6a82351	Patch
https://git.kernel.org/stable/c/18216b8ab6904753eaf31baf453cb02ecd202ba4	Patch
https://git.kernel.org/stable/c/4c03e6eb98443dc4d6d422a9780034a5b75376b4	Patch
https://git.kernel.org/stable/c/ec427dc5286da1ed08f2d510e2147a7581b0cb02	Patch
https://git.kernel.org/stable/c/ff734dbd9e2432601a6dcd167cfb0bf8a36d1880	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::

History

No history.

Information

Published : 2026-06-24 08:16

Updated : 2026-07-08 20:31

NVD link : CVE-2026-52936

Mitre link : CVE-2026-52936

CVE.ORG link : CVE-2026-52936

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-noinfo

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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": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "EF97161C-1BB5-4ADC-A7BA-2A18D7A44511", "versionEndExcluding": "6.6.141", "versionStartIncluding": "4.2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "C918746B-DE6F-448F-A93E-A04C5481688D", "versionEndExcluding": "6.12.91", "versionStartIncluding": "6.7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "96D99E49-380D-43AB-BDBA-25C3AD018A9C", "versionEndExcluding": "6.18.33", "versionStartIncluding": "6.13"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "A13475D2-59BF-4716-94B5-7C1D239A2CF4", "versionEndExcluding": "7.0.10", "versionStartIncluding": "6.19"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}