{"id":"AZL-68510","summary":"CVE-2025-39994 affecting package kernel for versions less than 6.6.112.1-1","details":"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 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 -\u003e tuner]","modified":"2026-04-01T05:21:25.725213Z","published":"2025-10-15T08:15:37Z","upstream":["CVE-2025-39994"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-39994"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.112.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-68510.json"}}],"schema_version":"1.7.5"}