CVE-2026-23445 Linux CVE debrief

Who should care

Defenders responsible for Linux kernel systems, particularly those utilizing XDP TX timestamping, should assess exposure and apply patches or updates as necessary to prevent potential page faults and system instability.

Why it matters

CVE-2026-23445 is a high-severity vulnerability in the Linux kernel's igc driver that can cause page faults during XDP TX timestamping. Defenders should prioritize patching affected systems to prevent potential system instability or DoS.

• Potential system crashes or instability due to page faults during XDP TX timestamping.
• Increased risk of denial-of-service (DoS) or system hang due to IRQ handler accessing stale xsk meta data.
• Need for verification of Linux kernel versions and XDP TX timestamping usage to determine exposure.
• Priority for applying patches or updates to prevent exploitation.

Technical summary

The Linux kernel vulnerability CVE-2026-23445, with a CVSS score of 7.8, has been resolved. The issue was related to the igc driver and caused a page fault during XDP TX timestamps handling when the TX ring was shut down. The fix involves cleaning up stale xsk meta data on TX shutdown. This vulnerability affects Linux kernel systems using XDP TX timestamping, and defenders should prioritize verifying and applying patches for affected Linux kernel versions. The vulnerability is caused by the xsk_meta pointers being left behind during TX ring shutdown, leading to the IRQ handler attempting to access them.

Defensive priority

Defenders should prioritize verifying and applying patches for Linux kernel versions affected by this vulnerability, particularly those using XDP TX timestamping.

Recommended defensive actions

• Verify Linux kernel versions in use and assess exposure based on the provided affected versions.
• Apply patches or updates provided by the Linux kernel maintainers to address the vulnerability.
• Review system configurations and XDP TX timestamping usage to determine potential impact.
• Monitor system logs for potential exploitation attempts or related errors.
• Perform a thorough review of the Linux kernel version used in your environment to identify potential exposure.
• Consider implementing compensating controls for exposed systems while remediation is scheduled and verified.
• Track exceptions, retest remediated assets, and close the item only after evidence is documented.

Evidence notes

The vulnerability is caused by the xsk_meta pointers being left behind during TX ring shutdown, leading to the IRQ handler attempting to access them. This issue is resolved by cleaning up stale xsk meta data on TX shutdown.

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.