PT-2026-34988 · Linux · Linux Kernel

Published 2026-04-24 · Updated 2026-04-28 · CVE-2026-31636

Positive Technologies (AI Summary)

CVSS v3.1

9.1

Critical

Base vector

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

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

Description An out-of-bounds read exists in the rxrpc component. The function rxgk verify authenticator() copies auth len bytes into a temporary buffer and passes the parser limit to rxgk do verify authenticator(). Because the pointer is a be32 *, the parser end pointer is inflated by a factor of four, allowing malformed RESPONSE authenticators to read past the allocated kmalloc() buffer.

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

Out of bounds Read

Weakness Enumeration

CWE-125

Related Identifiers

CVE-2026-31636

Affected Products

Linux Kernel

References · 11

• https://git.kernel.org/stable/c/20a188775a9a9982d1987e12660d9b44b40a6c99 · Patch
• https://security-tracker.debian.org/tracker/CVE-2026-31636 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-31636 · Vendor Advisory
• https://git.kernel.org/stable/c/3e3138007887504ee9206d0bfb5acb062c600025 · Patch
• https://git.kernel.org/stable/c/7875f3d9777bd4e9892c4db830571ab8ac2044c0 · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2026-31636 · Security Note
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-31636 · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-31636 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2026-31636 · Security Note
• https://twitter.com/CVEnew/status/2047731949066666032 · Twitter Post
• https://git.kernel.org/linus/3e3138007887504ee9206d0bfb5acb062c600025 · Note