---
id: CVE-2026-31633
title: 'rxrpc: Fix integer overflow in rxgk_verify_response()'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  rxrpc: Fix integer overflow in rxgk_verify_response()

  In rxgk_verify_response(), there's a potential integer overflow due to
  rounding up token_len before checking it, …
severity: critical
cvss: 9.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
cvssSource: cna
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 9d1d2b59341f58126a69b51f9f5f8ccb9f12e54a <
    1f864d9daaf622aeaa774404fd51e7d6a435b046
  - >-
    Linux >= 9d1d2b59341f58126a69b51f9f5f8ccb9f12e54a <
    c1e242beb6b1efc3c286f617e8d940c8fbf2ed41
  - >-
    Linux >= 9d1d2b59341f58126a69b51f9f5f8ccb9f12e54a <
    699e52180f4231c257821c037ed5c99d5eb0edb8
  - Linux 6.16
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: total
  timestamp: '2026-10-16T15:11:22.560304Z'
published: '2026-04-24'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T15:20:17.544Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-31633'
references:
  - url: 'https://git.kernel.org/stable/c/1f864d9daaf622aeaa774404fd51e7d6a435b046'
  - url: 'https://git.kernel.org/stable/c/c1e242beb6b1efc3c286f617e8d940c8fbf2ed41'
  - url: 'https://git.kernel.org/stable/c/699e52180f4231c257821c037ed5c99d5eb0edb8'
tags:
  - cve.org
epss: 0.00469
epssPercentile: 0.39178
ingestedAt: '2026-10-16T17:24:46.665Z'
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

rxrpc: Fix integer overflow in rxgk_verify_response()

In rxgk_verify_response(), there's a potential integer overflow due to
rounding up token_len before checking it, thereby allowing the length check to
be bypassed.

Fix this by checking the unrounded value against len too (len is limited as
the response must fit in a single UDP packet).

## Affected

- `Linux >= 9d1d2b59341f58126a69b51f9f5f8ccb9f12e54a < 1f864d9daaf622aeaa774404fd51e7d6a435b046`
- `Linux >= 9d1d2b59341f58126a69b51f9f5f8ccb9f12e54a < c1e242beb6b1efc3c286f617e8d940c8fbf2ed41`
- `Linux >= 9d1d2b59341f58126a69b51f9f5f8ccb9f12e54a < 699e52180f4231c257821c037ed5c99d5eb0edb8`
- `Linux 6.16`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.