CVE-2026-31514 Linux CVE debrief

Who should care

Linux kernel maintainers, users, and administrators should assess exposure and apply patches or updates to prevent potential issues. This includes operators managing Linux-based systems, platform administrators, vulnerability management teams, and security teams responsible for monitoring and mitigating Linux kernel vulnerabilities.

Why it matters

CVE-2026-31514 is a Linux kernel vulnerability that has been resolved. It addresses an issue where fileio bio failed in short read cases for file-backed mounts. Linux kernel maintainers and users should assess exposure and apply patches or updates to prevent potential issues.

• Verify Linux kernel versions and apply patches to prevent potential issues.
• Monitor Linux kernel updates and patches for future vulnerabilities.
• Assess exposure and prioritize patching for Linux kernel versions 6.12.75, 6.18.14, and 6.19.4.

Technical summary

The Linux kernel vulnerability (CVE-2026-31514) arises from fileio bio failure in short read cases for file-backed mounts. When IO requests handled by vfs_iocb_iter_read() are interrupted by SIGKILL, unused folios in bio are unexpectedly marked as uptodate. The issue has been addressed by setting short read bio with an error directly. Affected versions include 6.12.75, 6.18.14, and 6.19.4; resolved versions include 6.12.80, 6.18.21, and 6.19.11.

Defensive priority

Medium priority for Linux kernel maintainers and users, as the vulnerability has been resolved and patches are available.

Recommended defensive actions

• Review and apply available patches for Linux kernel versions 6.12.75, 6.18.14, and 6.19.4.
• Update Linux kernel to versions 6.12.80, 6.18.21, or 6.19.11, or later.
• Monitor Linux kernel updates and patches for future vulnerabilities.
• Verify Linux kernel versions and apply patches to prevent potential issues.
• Assess exposure and prioritize patching for Linux kernel versions.
• Review 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 was introduced in Linux kernel versions 6.12.75, 6.18.14, and 6.19.4, and has been resolved in versions 6.12.80, 6.18.21, and 6.19.11. The CVE record and NVD entry provide details on the vulnerability and available patches.

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.