CVE-2026-64251 (GCVE-0-2026-64251)

Vulnerability from cvelistv5 – Published: 2026-07-24 15:31 – Updated: 2026-08-17 04:52
VLAI
Title
pwrseq: core: fix use-after-free in pwrseq_debugfs_seq_next()
Summary
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.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6653 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 249ebf3f65f8530beb2cbfb91bff1d83ba88d23c , < ba0b9f04c7a5f9887b8ce672eaf049502c0548ec (git)
Affected: 249ebf3f65f8530beb2cbfb91bff1d83ba88d23c , < e91df6d273445c03f5aa302bfe147eda33d45794 (git)
Affected: 249ebf3f65f8530beb2cbfb91bff1d83ba88d23c , < 73569a44fca2992f0ca4a4c0104069741b9873a0 (git)
Affected: 249ebf3f65f8530beb2cbfb91bff1d83ba88d23c , < 257595adf9dac15ae1edd9d07753fbc576a7583d (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.11
Unaffected: 0 , < 6.11 (semver)
Unaffected: 6.12.95 , ≤ 6.12.* (semver)
Unaffected: 6.18.38 , ≤ 6.18.* (semver)
Unaffected: 7.1.3 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
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      "cve": "CVE-2026-64251",
      "id": "CVE-2026-64251",
      "initial_release_date": "2026-07-24T00:00:00+00:00",
      "product_status:known_affected": "1",
      "product_status:known_not_affected": "199",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: Linux kernel: Use-after-free in pwrseq_debugfs_seq_next() can lead to denial of service",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64251.json",
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}



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