CVE-2026-23368: Linux kernel · net: phy: register phy led_triggers during probe to avoid AB-BA deadlock
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.5 Medium · patch available : update Linux kernel when convenient.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 0% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 25 Mar 2026
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 25.10linuxpkg:deb/ubuntu/linux@6.17.0-40.40?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-awspkg:deb/ubuntu/linux-aws@6.17.0-1019.19?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azurepkg:deb/ubuntu/linux-azure@6.17.0-1020.20?arch=source&distro=questingOther threats | 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 25.10linux-gcppkg:deb/ubuntu/linux-gcp@6.17.0-1020.22?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-oraclepkg:deb/ubuntu/linux-oracle@6.17.0-1018.18?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 should be applied. The fix changes the timing of PHY LED trigger registration to avoid the AB-BA deadlock. Users should update to patched Linux kernel versions as provided by their distribution vendors. No additional mitigation is required beyond applying the official patch.
Description
A deadlock vulnerability in the Linux kernel's PHY LED trigger registration was resolved. The issue occurs when both LEDS_TRIGGER_NETDEV and LED_TRIGGER_PHY are enabled, causing an AB-BA deadlock due to conflicting lock acquisition orders involving triggers_list_lock and rtnl_mutex. The vulnerability affects specific Linux kernel versions and has been fixed by changing the registration timing of PHY LED triggers to avoid holding conflicting locks simultaneously.
References
- ubuntu.com/security/CVE-2026-23368 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-23368 (opens in a new tab)
- git.kernel.org/linus/c8dbdc6e380e7e96a51706db3e4b7870d8a9402d (opens in a new tab)
- git.kernel.org/stable/c/241cd64cf2e32b28ead151b1795cd8fef2b6e482 (opens in a new tab)
- git.kernel.org/stable/c/2764dcb3c35de4410f642afc62cf979727470575 (opens in a new tab)
- git.kernel.org/stable/c/c33523b8fd2d4c504ada18cd93f511f2a8f84217 (opens in a new tab)
- git.kernel.org/stable/c/c6ffc2d2338d325e1edd0c702e3ee623aa5fdc6a (opens in a new tab)
- git.kernel.org/stable/c/c8dbdc6e380e7e96a51706db3e4b7870d8a9402d (opens in a new tab)
- git.kernel.org/stable/c/cde2d0b5ab5d03b5b6f17d4f654d8b30ccf36757 (opens in a new tab)
- ubuntu.com/security/notices/USN-8567-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8574-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8575-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8576-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8574-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8595-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8596-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8575-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8576-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8597-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8595-2 (opens in a new tab)