CVE-2026-74667 Linux CVE debrief

Who should care

Linux kernel developers and maintainers, Linux distribution maintainers, system administrators responsible for Linux kernel updates and security patches, and security teams responsible for monitoring and responding to potential security incidents. These individuals should be aware of the vulnerability and take steps to mitigate its impact, including applying patches, monitoring system logs, and updating asset inventory.

Why it matters

A vulnerability in the Linux kernel's net/packet implementation could allow a local attacker to cause an out-of-bounds memory access. Defenders should verify and apply patches, monitor for potential issues, and update Linux kernel versions as necessary.

• Potential crashes or information disclosure due to out-of-bounds memory access.
• Verification of Linux kernel versions and patch application to prevent potential issues.
• Monitoring for potential issues related to the packet-socket transmit path.

Technical summary

The Linux kernel's net/packet implementation does not properly reset the MAC header on the packet-socket transmit path under certain conditions. This could lead to an out-of-bounds memory access when a driver reads the MAC header on transmit. The issue arises from the packet_parse_headers() function not resetting the MAC header for certain types of frames, including SOCK_RAW frames with a bound protocol, SOCK_DGRAM frames, and the legacy SOCK_PACKET path. This vulnerability could be exploited by a local attacker to gain unauthorized access to sensitive information or disrupt system operations.

Defensive priority

Medium

Recommended defensive actions

• Review and apply the provided patches to ensure the MAC header is properly reset on the packet-socket transmit path.
• Verify the Linux kernel version and update to a patched version if necessary.
• Monitor for potential crashes or information disclosure related to the packet-socket transmit path.
• Perform a thorough review of system logs to detect any potential exploitation attempts.
• Update asset inventory to track systems that may be affected by this vulnerability.
• Consider implementing compensating controls, such as additional monitoring or access restrictions, for systems that cannot be patched immediately.
• technicalSummary

Evidence notes

The CVE record and associated source item provide details on the vulnerability, including its description and affected versions. However, the corpus does not establish specific exploitation instances or impact.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.