{"id":"CVE-2026-52936","summary":"crypto: jitterentropy - replace long-held spinlock with mutex","details":"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.","modified":"2026-07-10T03:54:04.653070603Z","published":"2026-06-24T07:14:26.649Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/52xxx/CVE-2026-52936.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/01d798e9feb30212952d4e992801ba6bd6a82351"},{"type":"WEB","url":"https://git.kernel.org/stable/c/18216b8ab6904753eaf31baf453cb02ecd202ba4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4c03e6eb98443dc4d6d422a9780034a5b75376b4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ec427dc5286da1ed08f2d510e2147a7581b0cb02"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ff734dbd9e2432601a6dcd167cfb0bf8a36d1880"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/52xxx/CVE-2026-52936.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-52936"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"bb5530e4082446aac3a3d69780cd4dbfa4520013"},{"fixed":"18216b8ab6904753eaf31baf453cb02ecd202ba4"},{"fixed":"4c03e6eb98443dc4d6d422a9780034a5b75376b4"},{"fixed":"ff734dbd9e2432601a6dcd167cfb0bf8a36d1880"},{"fixed":"ec427dc5286da1ed08f2d510e2147a7581b0cb02"},{"fixed":"01d798e9feb30212952d4e992801ba6bd6a82351"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-52936.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.2.0"},{"fixed":"6.6.141"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.91"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.33"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.0.10"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-52936.json"}}],"schema_version":"1.7.5"}