CVE-2026-68193
Description
A flaw was found in the Linux kernel. The mt7925 Wi-Fi driver incorrectly dispatches a memory-mapped I/O (MMIO) specific event to non-MMIO buses, such as USB. This improper handling leads to a NULL pointer dereference when attempting to clean up DMA transmit queues. A remote attacker could exploit this vulnerability by sending specially crafted Wi-Fi packets, causing a system crash and resulting in a denial of service.
Statement
This issue affects MediaTek mt7925 on non-MMIO buses (e.g. USB). MMIO-only TXRX_NOTIFY events are dispatched to mt7925_mac_tx_free(), calling unsupported queue ops. Systems without mt7925 USB Wi-Fi are not affected.
Mitigation
To mitigate this issue, prevent the mt7925e module from loading. See https://access.redhat.com/solutions/41278 for instructions.
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 | 5.5 | N/A | N/A |
| Attack Vector | Local | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | Low | N/A | N/A |
| User Interaction | None | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | None | N/A | N/A |
| Integrity Impact | None | N/A | N/A |
| Availability Impact | High | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Crash, Exit, or Restart
NULL pointer dereferences usually result in the failure of the process unless exception handling (on some platforms) is available and implemented. Even when exception handling is being used, it can still be very difficult to return the software to a safe state of operation.
Integrity,Confidentiality
Technical Impact: Execute Unauthorized Code or Commands; Read Memory; Modify Memory
In rare circumstances, when NULL is equivalent to the 0x0 memory address and privileged code can access it, then writing or reading memory is possible, which may lead to code execution.
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
