CVE-2026-31637

Description

A flaw was found in the Linux kernel's rxrpc subsystem. A remote attacker could exploit this by sending a malformed RXKAD response ticket. This ticket, with a non-block-aligned length, would cause decryption to fail, yet the system would proceed to process attacker-controlled data. This could lead to a denial of service, causing the connection to be aborted.

Statement

Malformed RXKAD tickets that cannot decrypt are now rejected instead of confusing later crypto paths. Red Hat classifies this as rxrpc hardening against untrusted peers.

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 Score5.5N/A9.8
Attack VectorLocalN/ANetwork
Attack ComplexityLowN/ALow
Privileges RequiredLowN/ANone
User InteractionNoneN/ANone
ScopeUnchangedN/AUnchanged
ConfidentialityNoneN/AHigh
Integrity ImpactNoneN/AHigh
Availability ImpactHighN/AHigh

Vector

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

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

Understanding the Weakness (CWE)

Availability,Integrity

Technical Impact: Unexpected State; DoS: Crash, Exit, or Restart

An unexpected return value could place the system in a state that could lead to a crash or other unintended behaviors.

Frequently Asked Questions

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