PT-2026-34657 · Linux · Linux Kernel

Published 2026-04-23 · Updated 2026-05-26 · CVE-2026-31531

Positive Technologies (AI Summary)

CVSS v3.1

5.5

Medium

Base vector

AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description An issue exists when querying a nexthop object via RTM GETNEXTHOP. The kernel allocates a fixed-size skb (socket buffer) using NLMSG GOODSIZE, which is insufficient for large nexthop groups, such as those containing 512 nexthops. This leads to a warning splat in the rtm get nexthop() function.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Related Identifiers

CVE-2026-31531

ECHO-F902-DE2E-99DE

Affected Products

Linux Kernel

References · 16

• https://git.kernel.org/stable/c/40bd39e383a0478fd5c221f393df05fd9d70cfbc · Patch
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-31531 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-31531 · Vendor Advisory
• https://osv.dev/vulnerability/ROOT-OS-UBUNTU-2204-CVE-2026-31531 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-31531 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2026-31531 · Security Note
• https://git.kernel.org/stable/c/635038fe19db391117e66b46bdc2b6e447ac801d · Patch
• https://osv.dev/vulnerability/BELL-CVE-2026-31531 · Vendor Advisory
• https://git.kernel.org/stable/c/14cf0cd35361f4e94824bf8a42f72713d7702a73 · Patch
• https://security-tracker.debian.org/tracker/CVE-2026-31531 · Vendor Advisory
• https://git.kernel.org/stable/c/615517f3f8d53b0cf41507c7599971e17adfdfa5 · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2026-31531 · Security Note
• https://docs.bell-sw.com/security/cves/CVE-2026-31531 · Note
• https://git.kernel.org/linus/14cf0cd35361f4e94824bf8a42f72713d7702a73 · Note
• https://twitter.com/CVEnew/status/2047359857997521201 · Twitter Post