CVE-2026-31635

Aliases:UBUNTU-CVE-2026-31635DEBIAN-CVE-2026-31635
Advisory lineage Upstream: 0 Downstream: 5
Modified
Published: 24 Apr 2026, 14:44
Last modified:05 Aug 2026, 12:23

Vulnerability Summary

Overall Risk (default)
medium
40/100
CVSS Score
7.5 HIGH
v3.1 (cve.org)
EPSS Score
0.92% LOW
1% probability +0.11%
KEV
Not listed
Ransomware
No reports
Public exploits
1 found
Dark Web
Not detected

Timeline

24 Apr 2026, 14:44
Published
Vulnerability first disclosed
05 Aug 2026, 12:23
Last Modified
Vulnerability information updated

Description

In the Linux kernel, the following vulnerability has been resolved: rxrpc: fix oversized RESPONSE authenticator length check rxgk_verify_response() decodes auth_len from the packet and is supposed to verify that it fits in the remaining bytes. The existing check is inverted, so oversized RESPONSE authenticators are accepted and passed to rxgk_decrypt_skb(), which can later reach skb_to_sgvec() with an impossible length and hit BUG_ON(len). Decoded from the original latest-net reproduction logs with scripts/decode_stacktrace.sh: RIP: __skb_to_sgvec() [net/core/skbuff.c:5285 (discriminator 1)] Call Trace: skb_to_sgvec() [net/core/skbuff.c:5305] rxgk_decrypt_skb() [net/rxrpc/rxgk_common.h:81] rxgk_verify_response() [net/rxrpc/rxgk.c:1268] rxrpc_process_connection() [net/rxrpc/conn_event.c:266 net/rxrpc/conn_event.c:364 net/rxrpc/conn_event.c:386] process_one_work() [kernel/workqueue.c:3281] worker_thread() [kernel/workqueue.c:3353 kernel/workqueue.c:3440] kthread() [kernel/kthread.c:436] ret_from_fork() [arch/x86/kernel/process.c:164] Reject authenticator lengths that exceed the remaining packet payload.

CVSS Metrics

  • v4.0MEDIUMScore: 6.9CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
  • v3.1HIGHScore: 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Trends

Current EPSS score: 0.92% Percentile: 59%

Techniques & Countermeasures

  • CWE-130Improper Handling of Length Parameter Inconsistency

    The product parses a formatted message or structure, but it does not handle or incorrectly handles a length field that is inconsistent with the actual length of the associated data.

Affected Systems

  • debianlinux

    < 6.19.13-1

  • ubuntulinux

    < 6.17.0-40.40

  • ubuntulinux-allwinner-5.19

    all

  • ubuntulinux-aws

    < 6.17.0-1019.19

  • ubuntulinux-aws-5.0

    all

  • ubuntulinux-aws-5.11

    all

  • ubuntulinux-aws-5.13

    all

  • ubuntulinux-aws-5.19

    all

  • ubuntulinux-aws-5.3

    all

  • ubuntulinux-aws-5.8

    all

  • ubuntulinux-aws-6.14

    all

  • ubuntulinux-aws-6.17

    < 6.17.0-1019.19~24.04.1

  • ubuntulinux-aws-6.2

    all

  • ubuntulinux-aws-6.5

    all

  • ubuntulinux-azure

    all | all

  • ubuntulinux-azure-5.11

    all

  • ubuntulinux-azure-5.13

    all

  • ubuntulinux-azure-5.19

    all

  • ubuntulinux-azure-5.3

    all

  • ubuntulinux-azure-5.8

    all

  • ubuntulinux-azure-6.11

    all

  • ubuntulinux-azure-6.17

    < 6.17.0-1021.21~24.04.1

  • ubuntulinux-azure-6.2

    all

  • ubuntulinux-azure-6.5

    all

  • ubuntulinux-azure-edge

    all

  • ubuntulinux-azure-fde

    all | all | all

  • ubuntulinux-azure-fde-5.19

    all

  • ubuntulinux-azure-fde-6.2

    all

  • ubuntulinux-azure-fde-7.0

    all

  • ubuntulinux-bluefield

    all

  • ubuntulinux-gcp

    all | < 6.17.0-1020.22

  • ubuntulinux-gcp-5.11

    all

  • ubuntulinux-gcp-5.13

    all

  • ubuntulinux-gcp-5.19

    all

  • ubuntulinux-gcp-5.3

    all

  • ubuntulinux-gcp-5.8

    all

  • ubuntulinux-gcp-6.11

    all

  • ubuntulinux-gcp-6.14

    all

  • ubuntulinux-gcp-6.17

    < 6.17.0-1020.22~24.04.1

  • ubuntulinux-gcp-6.2

    all

  • ubuntulinux-gcp-6.5

    all

  • ubuntulinux-gke

    all

  • ubuntulinux-gke-4.15

    all

  • ubuntulinux-gke-5.15

    all

  • ubuntulinux-gke-5.4

    all

  • ubuntulinux-gkeop

    all

  • ubuntulinux-gkeop-5.15

    all

  • ubuntulinux-gkeop-5.4

    all

  • ubuntulinux-hwe

    all

  • ubuntulinux-hwe-5.11

    all

Showing first 50 affected entries in server-rendered view.

References (16)