CVE-2025-40347: Linux kernel · net: enetc: fix the deadlock of enetc_mdio_lock
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.5 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
- 0.5% chance of exploitation in 30 days – higher than 44% 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:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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
A patch is available that fixes the deadlock by preventing recursive acquisition of the enetc_mdio_lock. Users should apply the official Linux kernel updates that include this fix. The Ubuntu security advisory USN-8029-1 confirms the availability of this fix in updated kernel versions.
Description
A deadlock vulnerability in the Linux kernel's enetc network driver was fixed. The issue was caused by recursive acquisition of the enetc_mdio_lock read lock, leading to thread hangs on certain platforms after applying a workaround. The deadlock occurs when a higher-priority writer waits for a lock held by a reader that is itself blocked by the writer. The fix prevents recursive lock acquisition to avoid deadlock.
References
- ubuntu.com/security/CVE-2025-40347 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-40347 (opens in a new tab)
- git.kernel.org/linus/50bd33f6b3922a6b760aa30d409cae891cec8fb5 (opens in a new tab)
- git.kernel.org/stable/c/1f92f5bd057a4fad9dab6af17963cdd21e5da6ed (opens in a new tab)
- git.kernel.org/stable/c/2781ca82ce8cad263d80b617addb727e6a84c9e5 (opens in a new tab)
- git.kernel.org/stable/c/2e55a49dc3b2a6b23329e4fbbd8a5feb20e220aa (opens in a new tab)
- git.kernel.org/stable/c/50bd33f6b3922a6b760aa30d409cae891cec8fb5 (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)
- ubuntu.com/security/notices/USN-8095-5 (opens in a new tab)