PT-2026-30150 · Linux · Linux Kernel

Published 2026-04-03 · Updated 2026-05-28 · CVE-2026-23455

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 The Linux kernel contains a flaw within the netfilter module, specifically in the nf conntrack h323 component. The DecodeQ931() function is susceptible to an out-of-bounds read condition. This occurs when the UserUserIE code path processes a packet with an encoded length of 0. The length is decremented by 1, resulting in a wrap-around to -1, which is then incorrectly used as a large value in the decoder. This can lead to reading data outside the allocated memory boundaries.

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

ALSA-2026:21706

ALSA-2026:21745

CVE-2026-23455

ECHO-0A50-5C88-4815

OESA-2026-2172

OESA-2026-2173

OESA-2026-2176

Affected Products

Linux Kernel

References · 89

• https://cve.org/CVERecord?id=CVE-2026-23455 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-23407 · Security Note
• https://git.kernel.org/stable/c/633e8f87dad32263f6a57dccdb873f042c062111 · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2026-23406 · Security Note
• https://git.kernel.org/stable/c/2121f5fbe88daff0f1fc5bc47d359426c74b86b0 · Patch
• https://git.kernel.org/stable/c/f173d0f4c0f689173f8cdac79991043a4a89bf66 · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2026-31389 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-23452 · Security Note
• https://ubuntu.com/security/CVE-2026-23455 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-23378 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-23458 · Security Note
• https://osv.dev/vulnerability/ALSA-2026:21706 · Vendor Advisory
• https://errata.almalinux.org/8/ALSA-2026-21706.html · Vendor Advisory
• https://osv.dev/vulnerability/BELL-CVE-2026-23455 · Vendor Advisory
• https://osv.dev/vulnerability/ROOT-OS-UBUNTU-2204-CVE-2026-23455 · Vendor Advisory