CVE-2025-39908: Linux kernel · net: dev_ioctl: take ops lock in hwtstamp lower paths
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High.
Data as of 26 Oct 2026, 13:47 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 3% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
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 1 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
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde@6.17.0-1017.17?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinuxpkg:deb/ubuntu/linux@6.8.0-136.136?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-awspkg:deb/ubuntu/linux-aws@6.8.0-1060.63?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-aws-6.14pkg:deb/ubuntu/linux-aws-6.14@6.14.0-1018.18~24.04.1?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure@6.8.0-1062.69?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-azure-6.11pkg:deb/ubuntu/linux-azure-6.11@6.11.0-1018.18~24.04.1?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
A fix for this vulnerability has been implemented in the Linux kernel. Users should update to a patched kernel version that addresses the locking inconsistency in the hwtstamp ioctl paths. Since the vulnerability affects specific kernel versions, upgrading beyond these versions or applying the official patches is recommended. No vendor advisory content was provided to indicate otherwise.
Description
A vulnerability in the Linux kernel related to the network device ioctl operations has been resolved. The issue involves inconsistent locking in hardware timestamp (hwtstamp) lower paths, where callbacks were expected to run under a per-device operations lock but did not consistently do so. This could lead to kernel warnings and potential instability. The vulnerability affects specific Linux kernel versions listed and has a CVSS score of 7.8, indicating a high impact on confidentiality, integrity, and availability.
References
- ubuntu.com/security/CVE-2025-39908 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-39908 (opens in a new tab)
- git.kernel.org/linus/686cab5a18e443e1d5f2abb17bed45837836425f (opens in a new tab)
- git.kernel.org/stable/c/2d92fa0cdc02291de57f72170e8b60cef0cf5372 (opens in a new tab)
- git.kernel.org/stable/c/686cab5a18e443e1d5f2abb17bed45837836425f (opens in a new tab)