PT-2026-37395 · Linux · Linux Kernel

Published 2026-05-06 · Updated 2026-06-01 · CVE-2026-43085

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 A flaw in the netfilter nfnetlink log component allows the leakage of four bytes of stale kernel heap data to userspace. This occurs when batching multiple NFLOG messages, where the nfulnl send() function appends an NLMSG DONE terminator using nlmsg put(). Because nlmsg put() only zeroes alignment padding and not the nfgenmsg payload itself, uninitialized data is exposed.

Recommendations Update the Linux kernel to a version where nfnl msg put() is used to build the NLMSG DONE terminator, ensuring the nfgenmsg payload is properly initialized via nfnl fill hdr().

Fix

Related Identifiers

CVE-2026-43085

Affected Products

Linux Kernel

References · 20

• https://git.kernel.org/stable/c/1f3083aec8836213da441270cdb1ab612dd82cf4 · Patch
• https://cve.org/CVERecord?id=CVE-2026-43085 · Security Note
• https://ubuntu.com/security/CVE-2026-43085 · Vendor Advisory
• https://osv.dev/vulnerability/BELL-CVE-2026-43085 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2026-43085 · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-43085 · Vendor Advisory
• https://git.kernel.org/stable/c/57cc509d82b46150a11dcecc8b25eaa177eda34d · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2026-43085 · Security Note
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-43085 · Vendor Advisory
• https://osv.dev/vulnerability/ROOT-OS-UBUNTU-2204-CVE-2026-43085 · Vendor Advisory
• https://git.kernel.org/stable/c/296f18e1c3a87c915a92ed27832d5040a22d1072 · Patch
• https://git.kernel.org/stable/c/15d209bccf9273b4a8b4e579ba0e92d065b6ec8c · Patch
• https://git.kernel.org/stable/c/368c22aea490f6f50df831b4f9e3623787686c5b · Patch
• https://git.kernel.org/stable/c/d552bcfca323d175664d7444989b04f55666978a · Patch
• https://git.kernel.org/stable/c/d1399632ba255d2e02c757af5d9f5d9279ce168c · Patch