CVE-2026-31474: Linux kernel · can: isotp: fix tx.buf use-after-free in isotp_sendmsg()
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 7.8 High · fixed in eec8a1b18a79600bd4419079dc0026c1db72a830 : patch Linux kernel soon.
Data as of 26 Oct 2026, 14:18 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.
- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Total control over the software or total information disclosure
CISA SSVC assessment, 2026-10-16.
- Patch
- Available – fixed in eec8a1b18a79600bd4419079dc0026c1db72a830, cb3d6efa78460e6d50bf68806d0db66265709f64, 9649d051e54413049c009638ec1dc23962c884a4 +2
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 22 Apr 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 |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in– |
AI-suggested
A fix is available and included in Linux kernel version 6.4 and later. Systems should upgrade to a fixed kernel version. For systems that do not require CAN ISO-TP functionality, the can_isotp kernel module can be blocklisted to prevent loading and mitigate the risk. Refer to the vendor advisory for detailed patch and mitigation instructions.
Description
CVE-2026-31474 is a use-after-free vulnerability in the Linux kernel's Controller Area Network (CAN) ISO-TP module. The flaw occurs when a local attacker sends a signal that interrupts a waiting process during socket close, causing premature freeing of a transmit buffer still in use. This can lead to memory corruption, potentially resulting in system crashes or unpredictable behavior. The issue is fixed by deferring the freeing of the buffer until socket destruction. A patch is available in Linux kernel version 6.4 and later.
References
- git.kernel.org/stable/c/cb3d6efa78460e6d50bf68806d0db66265709f64 (opens in a new tab)
- git.kernel.org/stable/c/9649d051e54413049c009638ec1dc23962c884a4 (opens in a new tab)
- git.kernel.org/stable/c/eec8a1b18a79600bd4419079dc0026c1db72a830 (opens in a new tab)
- git.kernel.org/stable/c/2e62e7051eca75a7f2e3d52d62ec10d7d7aa358c (opens in a new tab)
- git.kernel.org/stable/c/424e95d62110cdbc8fd12b40918f37e408e35a92 (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-31474 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2460646 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-31474.json (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:27731 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:27288 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:27789 (opens in a new tab)