PT-2026-36428 · Linux · Linux Kernel

Published 2026-05-01 · Updated 2026-05-26 · CVE-2026-43011

Positive Technologies (AI Summary)

CVSS v3.1

9.8

Critical

Base vector

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

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

Description A double free issue exists in the net/x25 component. When alloc skb fails within the x25 queue rx frame() function, the system calls kfree skb(skb) and returns an error. This error propagates through x25 state3 machine() and x25 process rx frame(), eventually leading x25 backlog rcv() to call kfree skb(skb) a second time on the same socket buffer (skb).

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

Double Free

Weakness Enumeration

CWE-415

Related Identifiers

CVE-2026-43011

ECHO-53A0-0203-A528

Affected Products

Linux Kernel

References · 21

• https://git.kernel.org/stable/c/c87dd137c0dad07cc55f98181ff380b0c23d2878 · Patch
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-43011 · Vendor Advisory
• https://git.kernel.org/stable/c/f782dd382203b2a8c4552a628431b7de65a19a7b · Patch
• https://cve.org/CVERecord?id=CVE-2026-43011 · Security Note
• https://git.kernel.org/stable/c/5d0aa038a90b30c9bedde0c41c1fdcd98ecb16e9 · Patch
• https://security-tracker.debian.org/tracker/CVE-2026-43011 · Vendor Advisory
• https://git.kernel.org/stable/c/fa1dbc93530b34fab0da9862426fe9c918c74dc0 · Patch
• https://osv.dev/vulnerability/ROOT-OS-UBUNTU-2204-CVE-2026-43011 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-43011 · Vendor Advisory
• https://git.kernel.org/stable/c/524371398d8463ea7e101fce2cbf3915645d1730 · Patch
• https://osv.dev/vulnerability/BELL-CVE-2026-43011 · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-43011 · Vendor Advisory
• https://git.kernel.org/stable/c/d10a26aa4d072320530e6968ef945c8c575edf61 · Patch
• https://git.kernel.org/stable/c/3f5e3005984645bf5bd129c6b13149879580b1fb · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2026-43011 · Security Note