{"id":"CVE-2025-39994","title":"media: tuner: xc5000: Fix use-after-free in xc5000_release","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nmedia: tuner: xc5000: Fix use-after-free in xc5000_release\n\nThe original code uses cancel_delayed_work() in xc5000_release(), which\ndoes not guarantee that the delayed …","severity":"high","cvss":7.3,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8 < bc4ffd962ce16a154c44c68853b9d93f5b6fc4b8","Linux >= f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8 < e2f5eaafc0306a76fb1cb760aae804b065b8a341","Linux >= f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8 < 3f876cd47ed8bca1e28d68435845949f51f90703","Linux >= f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8 < df0303b4839520b84d9367c2fad65b13650a4d42","Linux >= f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8 < 71ed8b81a4906cb785966910f39cf7f5ad60a69e","Linux >= f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8 < effb1c19583bca7022fa641a70766de45c6d41ac","Linux >= f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8 < 9a00de20ed8ba90888479749b87bc1532cded4ce","Linux >= f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8 < 4266f012806fc18e46da4a04d130df59a4946f93","Linux >= f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8 < 40b7a19f321e65789612ebaca966472055dab48c","Linux 3.16"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-15T21:55:59.194469Z"},"published":"2025-10-15","updated":"2026-10-15","sourceUpdated":"2026-10-15T22:02:35.851Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2025-39994","references":[{"url":"https://git.kernel.org/stable/c/bc4ffd962ce16a154c44c68853b9d93f5b6fc4b8"},{"url":"https://git.kernel.org/stable/c/e2f5eaafc0306a76fb1cb760aae804b065b8a341"},{"url":"https://git.kernel.org/stable/c/3f876cd47ed8bca1e28d68435845949f51f90703"},{"url":"https://git.kernel.org/stable/c/df0303b4839520b84d9367c2fad65b13650a4d42"},{"url":"https://git.kernel.org/stable/c/71ed8b81a4906cb785966910f39cf7f5ad60a69e"},{"url":"https://git.kernel.org/stable/c/effb1c19583bca7022fa641a70766de45c6d41ac"},{"url":"https://git.kernel.org/stable/c/9a00de20ed8ba90888479749b87bc1532cded4ce"},{"url":"https://git.kernel.org/stable/c/4266f012806fc18e46da4a04d130df59a4946f93"},{"url":"https://git.kernel.org/stable/c/40b7a19f321e65789612ebaca966472055dab48c"}],"tags":["cve.org"],"epss":0.00159,"epssPercentile":0.0508,"ingestedAt":"2026-10-15T22:48:25.536Z","slug":"CVE-2025-39994","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nmedia: tuner: xc5000: Fix use-after-free in xc5000_release\n\nThe original code uses cancel_delayed_work() in xc5000_release(), which\ndoes not guarantee that the delayed work item timer_sleep has fully\ncompleted if it was already running. This leads to use-after-free scenarios\nwhere xc5000_release() may free the xc5000_priv while timer_sleep is still\nactive and attempts to dereference the xc5000_priv.\n\nA typical race condition is illustrated below:\n\nCPU 0 (release thread)                 | CPU 1 (delayed work callback)\nxc5000_release()                       | xc5000_do_timer_sleep()\n  cancel_delayed_work()                |\n  hybrid_tuner_release_state(priv)     |\n    kfree(priv)                        |\n                                       |   priv = container_of() // UAF\n\nReplace cancel_delayed_work() with cancel_delayed_work_sync() to ensure\nthat the timer_sleep is properly canceled before the xc5000_priv memory\nis deallocated.\n\nA deadlock concern was considered: xc5000_release() is called in a process\ncontext and is not holding any locks that the timer_sleep work item might\nalso need. Therefore, the use of the _sync() variant is safe here.\n\nThis bug was initially identified through static analysis.\n\n[hverkuil: fix typo in Subject: tunner -> tuner]\n\n## Affected\n\n- `Linux >= f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8 < bc4ffd962ce16a154c44c68853b9d93f5b6fc4b8`\n- `Linux >= f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8 < e2f5eaafc0306a76fb1cb760aae804b065b8a341`\n- `Linux >= f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8 < 3f876cd47ed8bca1e28d68435845949f51f90703`\n- `Linux >= f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8 < df0303b4839520b84d9367c2fad65b13650a4d42`\n- `Linux >= f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8 < 71ed8b81a4906cb785966910f39cf7f5ad60a69e`\n- `Linux >= f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8 < effb1c19583bca7022fa641a70766de45c6d41ac`\n- `Linux >= f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8 < 9a00de20ed8ba90888479749b87bc1532cded4ce`\n- `Linux >= f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8 < 4266f012806fc18e46da4a04d130df59a4946f93`\n- `Linux >= f7a27ff1fb77e114d1059a5eb2ed1cffdc508ce8 < 40b7a19f321e65789612ebaca966472055dab48c`\n- `Linux 3.16`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":40,"depthScoreParts":{"impact":40.2,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}