CVE-2025-39701: Linux kernel · ACPI: pfr_update: Fix the driver update version check
Affects Linux kernelSource CVE Database V5
Not known to be exploited · fixed in cf0a88124e357bffda487cbf3cb612bb97eb97e4 : update Linux kernel when convenient.
Data as of 5 Nov 2026, 21:48 UTC
Rated Low by Threat Radar's AI analysis · No CVSS score from NVD or the CNA
Thin evidence
One scorer or none- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Limited control over the software or limited information exposure
CISA SSVC assessment, 2026-11-05.
- Patch
- Available – fixed in cf0a88124e357bffda487cbf3cb612bb97eb97e4, b00219888c11519ef75d988fa8a780da68ff568e, 908094681f645d3a78e18ef90561a97029e2df7b +2
Exploitation evidence
Disclosed: evidence found.
CVE published 5 Sep 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 5 Nov 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in– |
AI-suggested
A fix is available and has been applied in the Linux kernel versions identified by the fixed commit hashes. Users should update to a Linux kernel version that includes these fixes to resolve the vulnerability. No additional mitigation is required beyond applying the official patch.
Description
A vulnerability in the Linux kernel's ACPI pfr_update driver was fixed by correcting the version check logic. The driver previously used a runtime version check for firmware updates, which could cause update failures if the update binary had a lower runtime version number than the current one. The fix changes the check to use the security-version-number instead, ensuring proper update validation.
References
- git.kernel.org/stable/c/79300ff532bccbbf654992c7c0863b49a6c3973c (opens in a new tab)
- git.kernel.org/stable/c/cf0a88124e357bffda487cbf3cb612bb97eb97e4 (opens in a new tab)
- git.kernel.org/stable/c/b00219888c11519ef75d988fa8a780da68ff568e (opens in a new tab)
- git.kernel.org/stable/c/908094681f645d3a78e18ef90561a97029e2df7b (opens in a new tab)
- git.kernel.org/stable/c/8151320c747efb22d30b035af989fed0d502176e (opens in a new tab)
- lists.debian.org/debian-lts-announce/2025/10/msg00008.html (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-032379.html (opens in a new tab)