CVE-2026-23362
Description
A flaw was found in the Linux kernel's Controller Area Network (CAN) Broadcast Manager (BCM) module. When the RX_RTR_FRAME flag is set and a specific Remote Transmission Request (RTR) frame is received, the bcm_tx_lock was not properly initialized in the bcm_rx_setup() function. This missing initialization of the lock could lead to a race condition, potentially allowing a local attacker to cause a Denial of Service (DoS) by triggering system instability.
Statement
This flaw affects systems using CAN bus with the BCM (Broadcast Manager) socket. The missing spin_lock_init() for bcm_tx_lock in bcm_rx_setup() causes issues when RX_RTR_FRAME is used, as bcm_can_tx() accesses the uninitialized lock. Requires CAN interface and BCM socket usage with RTR frames.
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).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.5 | 5.5 | N/A |
| Attack Vector | Local | Local | N/A |
| Attack Complexity | Low | Low | N/A |
| Privileges Required | Low | Low | N/A |
| User Interaction | None | None | N/A |
| Scope | Unchanged | Unchanged | N/A |
| Confidentiality | None | None | N/A |
| Integrity Impact | None | None | N/A |
| Availability Impact | High | High | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Memory; Read Application Data
When reusing a resource such as memory or a program variable, the original contents of that resource may not be cleared before it is sent to an untrusted party.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
The uninitialized resource may contain values that cause program flow to change in ways that the programmer did not intend.
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
