CVE-2026-31474
Description
A flaw was found in the Linux kernel's Controller Area Network (CAN) ISO-TP (isotp) module. This vulnerability, known as a use-after-free, occurs when the system attempts to free a memory region while it is still being used. A local attacker could trigger this condition by sending a signal that interrupts a specific waiting process during a close operation. This can lead to memory corruption, potentially causing the system to crash (denial of service) or behave unpredictably.
Statement
This is an Important use-after-free flaw in the Linux kernel's Controller Area Network (CAN) ISO-TP module. A local attacker can trigger this vulnerability by interrupting a specific waiting process, potentially leading to memory corruption and system instability or denial of service. The impact is significant due to the potential for system compromise from a local user.
Mitigation
Systems which do not require it can blocklist the `can_isotp` module to prevent it from being loaded. See https://access.redhat.com/solutions/41278 for more information.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.8 | N/A | 7.8 |
| Attack Vector | Local | N/A | Local |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | Low | N/A | Low |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | High | N/A | High |
| Integrity Impact | High | N/A | High |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
cve.org: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Understanding the Weakness (CWE)
Integrity,Confidentiality,Availability
Technical Impact: Modify Application Data; Modify Memory; DoS: Crash, Exit, or Restart; Execute Unauthorized Code or Commands
It may be possible to cause data corruption and possibly execute arbitrary code by modifying global variables or data structures at unexpected times, violating the assumptions of code that uses this global data.
Access Control
Technical Impact: Gain Privileges or Assume Identity
If a signal handler interrupts code that is executing with privileges, it may be possible that the signal handler will also be executed with elevated privileges, possibly making subsequent exploits more severe.
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