{"id":"CVE-2026-64251","summary":"pwrseq: core: fix use-after-free in pwrseq_debugfs_seq_next()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\npwrseq: core: fix use-after-free in pwrseq_debugfs_seq_next()\n\npwrseq_debugfs_seq_next() declares 'next' with __free(put_device),\nwhich causes put_device() to be called on the returned pointer when\nthe variable goes out of scope.  This results in a use-after-free\nsince the seq_file framework receives a pointer whose reference has\nalready been dropped.\n\nSimply removing __free(put_device) would fix the UAF but would leak\nthe reference acquired by bus_find_next_device(), as stop() only\ncalls up_read(&pwrseq_sem) and never releases the device reference.\n\nFix this by making the reference counting consistent across all\nseq_file callbacks, matching the standard pattern used by PCI and\nSCSI:\n\n- start(): use get_device() so it returns a referenced pointer.\n- next(): explicitly put_device(curr) to release the previous\n  device's reference (no NULL check needed - the seq_file framework\n  only calls next() while the previous return was non-NULL).\n- stop(): put_device(data) to release the last iterated device's\n  reference, with a NULL guard since stop() may be called with NULL\n  when start() returned NULL or next() reached end-of-sequence.","modified":"2026-07-28T04:03:02.470513906Z","published":"2026-07-24T15:31:17.601Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64251.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/257595adf9dac15ae1edd9d07753fbc576a7583d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/73569a44fca2992f0ca4a4c0104069741b9873a0"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ba0b9f04c7a5f9887b8ce672eaf049502c0548ec"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e91df6d273445c03f5aa302bfe147eda33d45794"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64251.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64251"},{"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":"249ebf3f65f8530beb2cbfb91bff1d83ba88d23c"},{"fixed":"ba0b9f04c7a5f9887b8ce672eaf049502c0548ec"},{"fixed":"e91df6d273445c03f5aa302bfe147eda33d45794"},{"fixed":"73569a44fca2992f0ca4a4c0104069741b9873a0"},{"fixed":"257595adf9dac15ae1edd9d07753fbc576a7583d"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64251.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.11.0"},{"fixed":"6.12.95"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.38"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.3"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64251.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}