PatchSiren

PatchSiren cyber security CVE debrief

CVE-2026-31452 Linux CVE debrief

A HIGH severity vulnerability was found in the Linux kernel, with a CVSS score of 7.8. The vulnerability occurs when the file size of an inode with inline data exceeds the inline capacity during a truncate operation, causing the filesystem to enter an inconsistent state. This can lead to potential crashes and data corruption if not addressed. Linux kernel users and administrators should be aware of this vulnerability and take necessary actions to patch their systems.

Vendor
Linux
Product
Unknown
CVSS
HIGH 7.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-04-22
Original CVE updated
2026-07-14
Advisory published
2026-04-22
Advisory updated
2026-07-14

Who should care

Linux kernel users and administrators should be aware of this vulnerability and take necessary actions to patch their systems. This includes reviewing the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance. They should also plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.

Technical summary

The vulnerability occurs in the ext4 filesystem when the file size of an inode with inline data exceeds the inline capacity during a truncate operation. This can cause the filesystem to enter an inconsistent state, leading to a kernel BUG_ON(). The fix checks if the new size from setattr exceeds the inode's actual inline capacity and converts the file to extent-based storage before proceeding with the size change. This addresses the root cause by ensuring the inline data flag and file size remain consistent during truncate operations.

Defensive priority

High priority should be given to patching Linux kernel systems to prevent potential crashes and data corruption. This includes reviewing compensating controls for exposed systems while remediation is scheduled and verified.

Recommended defensive actions

  • Apply patches from Linux kernel maintainers
  • Inventory Linux kernel systems for potential exposure
  • Monitor for potential crashes and data corruption
  • Consider compensating controls such as filesystem checks and monitoring
  • Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance
  • Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed
  • Check relevant monitoring, detection, and logs for exposed assets that need extra review

Evidence notes

The CVE record was published on 2026-04-22T14:16:39.460Z and last modified on 2026-07-14T13:18:42.430Z. The NVD entry is currently Modified. This information is based on the provided source corpus and may not reflect the most up-to-date information. Users are advised to verify the details with the official sources.

Official resources

AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-04-22T14:16:39.460Z and has not been modified since then.