CVE-2026-23357: Linux kernel · can: mcp251x: fix deadlock in error path of mcp251x_open
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.5 Medium · fixed in 5.15.0-1112.119~20.04.1 : update Linux kernel when convenient.
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 5.15.0-1112.119~20.04.1, 5.15.0-1117.126~20.04.1, 5.15.0-1117.126~20.04.2 +63
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
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 this deadlock by changing the order of free_irq() and mutex release and setting a flag to force the IRQ handler to exit. Users should apply the official Linux kernel updates that include this fix. The Ubuntu security advisory USN-8567-1 confirms the availability of this fix in their kernel packages.
Description
A deadlock vulnerability in the Linux kernel's can: mcp251x driver was fixed. The issue occurred in the error path of the mcp251x_open() function where free_irq() was called while holding the mpc_lock mutex, potentially causing a deadlock if an interrupt handler was waiting on the same lock. The fix moves the free_irq() call after releasing the lock and sets a flag to ensure the IRQ handler exits promptly. This vulnerability affects specific Linux kernel versions and has a medium severity rating with a CVSS score of 5.5.
References
- ubuntu.com/security/CVE-2026-23357 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-23357 (opens in a new tab)
- git.kernel.org/linus/ab3f894de216f4a62adc3b57e9191888cbf26885 (opens in a new tab)
- git.kernel.org/stable/c/256f0cff6e946c570392bda1d01a65e789a7afd0 (opens in a new tab)
- git.kernel.org/stable/c/38063cc435b69d56e76f947c10d336fcb2953508 (opens in a new tab)
- git.kernel.org/stable/c/ab3f894de216f4a62adc3b57e9191888cbf26885 (opens in a new tab)
- git.kernel.org/stable/c/b73832292cd914e87a55e863ba4413a907e7db6b (opens in a new tab)
- git.kernel.org/stable/c/d27f12c3f5e85efc479896af4a69eccb37f75e8e (opens in a new tab)
- git.kernel.org/stable/c/e728f444c913a91d290d1824b4770780bbd6378e (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)