CVE-2025-39961: Linux kernel · iommu/amd/pgtbl: Fix possible race while increase page table level
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 8.8 High · fixed in 6.8.0-1050.53~22.04.1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 1% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 6.8.0-1050.53~22.04.1, 6.8.0-1051.57~22.04.1, 6.8.0-1058.65~22.04.1 +29
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 9 Oct 2025
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 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-aws-6.14pkg:deb/ubuntu/linux-aws-6.14?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-azure-6.11pkg:deb/ubuntu/linux-azure-6.11?arch=source&distro=nobleOther 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 implements sequence counters to prevent the race condition during page table level updates. Users should update to patched kernel versions as provided by their Linux distribution vendors. No additional mitigation is required beyond applying the official fix.
Description
A race condition vulnerability in the AMD IOMMU host page table implementation in the Linux kernel was fixed. The issue occurs due to unsynchronized reads of page table level data during page table level increases, potentially causing unmap operations to fail and upper layers to retry or log warnings. The flaw affects specific Linux kernel versions and has a high CVSS score of 8.8. A patch is available to address this by implementing sequence counters for lock-free read synchronization.
References
- ubuntu.com/security/CVE-2025-39961 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-39961 (opens in a new tab)
- git.kernel.org/linus/1e56310b40fd2e7e0b9493da9ff488af145bdd0c (opens in a new tab)
- git.kernel.org/stable/c/075abf0b1a958acfbea2435003d228e738e90346 (opens in a new tab)
- git.kernel.org/stable/c/1e56310b40fd2e7e0b9493da9ff488af145bdd0c (opens in a new tab)
- git.kernel.org/stable/c/7d462bdecb7d9c32934dab44aaeb7ea7d73a27a2 (opens in a new tab)
- git.kernel.org/stable/c/cd92c8ab336c3a633d46e6f35ebcd3509ae7db3b (opens in a new tab)
- ubuntu.com/security/notices/USN-8095-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8100-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8095-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8095-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8095-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8125-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8126-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8095-5 (opens in a new tab)
- ubuntu.com/security/notices/USN-8165-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8261-1 (opens in a new tab)