CVE-2026-64251: Linux kernel · pwrseq: core: fix use-after-free in pwrseq_debugfs_seq_next()
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in 7.0.0-31.31~24.04.1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 6% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 7.0.0-31.31~24.04.1, 7.0.0-31.31, 7.0.0-1012.12 +7
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 24 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
An official patch is available and should be applied to affected Linux kernel versions. The fix corrects the reference counting in the pwrseq subsystem to prevent use-after-free. Users should update to the patched kernel versions as provided by their Linux distribution vendors. No additional mitigation steps are required beyond applying the official fix.
Description
A use-after-free vulnerability in the Linux kernel's power sequencing core (pwrseq_debugfs_seq_next) was fixed. The issue involved inconsistent reference counting in seq_file callbacks, causing a pointer to be freed prematurely and then used. The fix aligns reference counting with standard patterns used in PCI and SCSI subsystems. This vulnerability affects specific Linux kernel versions and has a CVSS score of 7.8. A patch is available to address this flaw.
References
- ubuntu.com/security/CVE-2026-64251 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-64251 (opens in a new tab)
- git.kernel.org/linus/257595adf9dac15ae1edd9d07753fbc576a7583d (opens in a new tab)
- git.kernel.org/stable/c/257595adf9dac15ae1edd9d07753fbc576a7583d (opens in a new tab)
- git.kernel.org/stable/c/73569a44fca2992f0ca4a4c0104069741b9873a0 (opens in a new tab)
- git.kernel.org/stable/c/ba0b9f04c7a5f9887b8ce672eaf049502c0548ec (opens in a new tab)
- git.kernel.org/stable/c/e91df6d273445c03f5aa302bfe147eda33d45794 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8727-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-1 (opens in a new tab)