CVE-2026-31663

Description

A flaw was found in the Linux kernel's xfrm (IP eXtensible FRamework) subsystem. This vulnerability involves a race condition where a network device's reference is released too early during packet processing after asynchronous cryptography. This premature release can lead to the system attempting to access a deallocated device, potentially causing a system crash (Denial of Service).

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).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score7.8N/A7
Attack VectorLocalN/ALocal
Attack ComplexityLowN/AHigh
Privileges RequiredLowN/ALow
User InteractionNoneN/ANone
ScopeUnchangedN/AUnchanged
ConfidentialityHighN/AHigh
Integrity ImpactHighN/AHigh
Availability ImpactHighN/AHigh

Vector

Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

cve.org: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Understanding the Weakness (CWE)

Confidentiality

Technical Impact: Read Application Data; Read Memory

If the released resource is subsequently reused or reallocated, then a read operation on the original resource might access sensitive data that is associated with a different user or entity.

Availability

Technical Impact: DoS: Crash, Exit, or Restart

When the resource is released, the software might modify some of its structure, or close associated channels (such as a file descriptor). When the software later accesses the resource as if it is valid, the resource might not be in an expected state, leading to resultant errors that may lead to a crash.

Integrity,Confidentiality,Availability

Technical Impact: Execute Unauthorized Code or Commands; Modify Application Data; Modify Memory

When the resource is released, the software might modify some of its structure. This might affect logic in the sections of code that still assume the resource is active. If the released resource is related to memory and is used in a function call, or points to unexpected data in a write operation, then code execution may be possible upon subsequent accesses.

Frequently Asked Questions

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