CVE-2026-52936
crypto: jitterentropy - replace long-held spinlock with mutex
Description
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.
INFO
Published Date :
June 24, 2026, 8:16 a.m.
Last Modified :
July 8, 2026, 8:31 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Replace rng->jent_lock with a mutex.
- Update the Linux kernel to the latest version.
- Test the system for improved performance.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-52936.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-52936 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-52936
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-52936 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-52936 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Jul. 08, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Added CWE NVD-CWE-noinfo Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.7 up to (excluding) 6.12.91 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.13 up to (excluding) 6.18.33 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.19 up to (excluding) 7.0.10 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.2 up to (excluding) 6.6.141 Added Reference Type kernel.org: https://git.kernel.org/stable/c/01d798e9feb30212952d4e992801ba6bd6a82351 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/18216b8ab6904753eaf31baf453cb02ecd202ba4 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/4c03e6eb98443dc4d6d422a9780034a5b75376b4 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/ec427dc5286da1ed08f2d510e2147a7581b0cb02 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/ff734dbd9e2432601a6dcd167cfb0bf8a36d1880 Types: Patch -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jun. 24, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'bb5530e4082446aac3a3d69780cd4dbfa4520013', 'lessThan': '18216b8ab6904753eaf31baf453cb02ecd202ba4', 'versionType': 'git'}, {'status': 'affected', 'version': 'bb5530e4082446aac3a3d69780cd4dbfa4520013', 'lessThan': '4c03e6eb98443dc4d6d422a9780034a5b75376b4', 'versionType': 'git'}, {'status': 'affected', 'version': 'bb5530e4082446aac3a3d69780cd4dbfa4520013', 'lessThan': 'ff734dbd9e2432601a6dcd167cfb0bf8a36d1880', 'versionType': 'git'}, {'status': 'affected', 'version': 'bb5530e4082446aac3a3d69780cd4dbfa4520013', 'lessThan': 'ec427dc5286da1ed08f2d510e2147a7581b0cb02', 'versionType': 'git'}, {'status': 'affected', 'version': 'bb5530e4082446aac3a3d69780cd4dbfa4520013', 'lessThan': '01d798e9feb30212952d4e992801ba6bd6a82351', 'versionType': 'git'}], 'programFiles': ['crypto/jitterentropy-kcapi.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.2'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.2', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.6.141', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.91', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.33', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.0.10', 'versionType': 'semver', 'lessThanOrEqual': '7.0.*'}, {'status': 'unaffected', 'version': '7.1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['crypto/jitterentropy-kcapi.c'], 'defaultStatus': 'affected'}] Added Description 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. Added Reference https://git.kernel.org/stable/c/01d798e9feb30212952d4e992801ba6bd6a82351 Added Reference https://git.kernel.org/stable/c/18216b8ab6904753eaf31baf453cb02ecd202ba4 Added Reference https://git.kernel.org/stable/c/4c03e6eb98443dc4d6d422a9780034a5b75376b4 Added Reference https://git.kernel.org/stable/c/ec427dc5286da1ed08f2d510e2147a7581b0cb02 Added Reference https://git.kernel.org/stable/c/ff734dbd9e2432601a6dcd167cfb0bf8a36d1880