CVE-2026-64251

In the Linux kernel, the following vulnerability has been resolved: pwrseq: core: fix use-after-free in pwrseq_debugfs_seq_next() pwrseq_debugfs_seq_next() declares 'next' with __free(put_device), which causes put_device() to be called on the returned pointer when the variable goes out of scope. This results in a use-after-free since the seq_file framework receives a pointer whose reference has already been dropped. Simply removing __free(put_device) would fix the UAF but would leak the reference acquired by bus_find_next_device(), as stop() only calls up_read(&pwrseq_sem) and never releases the device reference. Fix this by making the reference counting consistent across all seq_file callbacks, matching the standard pattern used by PCI and SCSI: - start(): use get_device() so it returns a referenced pointer. - next(): explicitly put_device(curr) to release the previous device's reference (no NULL check needed - the seq_file framework only calls next() while the previous return was non-NULL). - stop(): put_device(data) to release the last iterated device's reference, with a NULL guard since stop() may be called with NULL when start() returned NULL or next() reached end-of-sequence.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/257595adf9dac15ae1edd9d07753fbc576a7583d	Patch
https://git.kernel.org/stable/c/73569a44fca2992f0ca4a4c0104069741b9873a0	Patch
https://git.kernel.org/stable/c/ba0b9f04c7a5f9887b8ce672eaf049502c0548ec	Patch
https://git.kernel.org/stable/c/e91df6d273445c03f5aa302bfe147eda33d45794	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::

History

No history.

Information

Published : 2026-07-24 16:16

Updated : 2026-08-17 05:17

NVD link : CVE-2026-64251

Mitre link : CVE-2026-64251

CVE.ORG link : CVE-2026-64251

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-416

Use After Free

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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."}], "lastModified": "2026-08-17T05:17:23.550", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "366244A3-18F7-431B-A01F-B0A69754C096", "versionEndExcluding": "6.12.95", "versionStartIncluding": "6.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "FA591B28-5D62-449E-BDBE-3C9391BF070A", "versionEndExcluding": "6.18.38", "versionStartIncluding": "6.13"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "9526B150-E2B3-4C6F-8AE5-1AF92B75AD9E", "versionEndExcluding": "7.1.3", "versionStartIncluding": "6.19"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}