CVE-2026-23455

Medium

Elevated severity or exploit probability.

CVSS base

9.1 CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

EPSS — probability of exploitation (30 days)

1.3%

70.0th percentile

CISA KEV

Not listed

Weakness / dates

CWE-125

Published 2026-04-03 · modified 2026-07-24

CVSS breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Attack Vector	N	Network
Attack Complexity	L	Low
Privileges Required	N	None
User Interaction	N	None
Scope	U	Unchanged
Confidentiality	H	High
Integrity	N	None
Availability	H	High

Timeline

2026-04-03 — Published (NVD)
2026-07-24 — Last modified (NVD)

Description

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_conntrack_h323: check for zero length in DecodeQ931() In DecodeQ931(), the UserUserIE code path reads a 16-bit length from the packet, then decrements it by 1 to skip the protocol discriminator byte before passing it to DecodeH323_UserInformation(). If the encoded length is 0, the decrement wraps to -1, which is then passed as a large value to the decoder, leading to an out-of-bounds read. Add a check to ensure len is positive after the decrement.

Affected

linux

References

Official: NVD · CVE.org