{"id":"CVE-2026-64251","title":"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…","summary":"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…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","published":"2026-07-24","updated":"2026-07-27","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-64251","references":[{"url":"https://git.kernel.org/stable/c/257595adf9dac15ae1edd9d07753fbc576a7583d","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/73569a44fca2992f0ca4a4c0104069741b9873a0","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ba0b9f04c7a5f9887b8ce672eaf049502c0548ec","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/e91df6d273445c03f5aa302bfe147eda33d45794","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd"],"epss":0.00117,"epssPercentile":0.01885,"ingestedAt":"2026-07-27T06:16:49.504Z","slug":"CVE-2026-64251","body":"## Overview\n\nIn 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}