CVE-2025-68171: Linux kernel · x86/fpu: Ensure XFD state on signal delivery
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 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 4% 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 +38
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 16 Dec 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 25.10linuxpkg:deb/ubuntu/linux?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-oraclepkg:deb/ubuntu/linux-oracle?arch=source&distro=questingOther 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 fix is available and has been released in updated Linux kernel versions. Users should apply the security updates provided by their Linux distribution, such as the Ubuntu security notice USN-8029-1, which includes this fix among others. No additional mitigation actions are required beyond applying the official patches.
Description
A vulnerability in the Linux kernel's x86/fpu subsystem related to signal delivery and XFD state handling has been resolved. The flaw involved a mismatch in the XFD state when a non-AMX task was preempted by an AMX-enabled task, potentially causing kernel warnings or instability. This issue was fixed by ensuring proper synchronization of the XFD state during signal delivery and task resumption.
References
- ubuntu.com/security/CVE-2025-68171 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-68171 (opens in a new tab)
- git.kernel.org/linus/388eff894d6bc5f921e9bfff0e4b0ab2684a96e9 (opens in a new tab)
- git.kernel.org/stable/c/1811c610653c0cd21cc9add14595b7cffaeca511 (opens in a new tab)
- git.kernel.org/stable/c/388eff894d6bc5f921e9bfff0e4b0ab2684a96e9 (opens in a new tab)
- git.kernel.org/stable/c/3f735419c4b43cde42e6d408db39137b82474e31 (opens in a new tab)
- git.kernel.org/stable/c/5b2619b488f1d08b960c43c6468dd0759e8b3035 (opens in a new tab)
- git.kernel.org/stable/c/eefbfb722042fc9210d2e0ac2b063fd1abf51895 (opens in a new tab)
- ubuntu.com/security/notices/USN-8029-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8030-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8029-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8048-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8029-3 (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)