CVE-2026-23455CWE-125

CVE-2026-23455

Critical · published April 3, 2026

CVSS v3.1
9.1
EPSS
1%
Percentile
71.0
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
9.1 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.01338 · 71.0th percentile
Weakness
CWE-125 · Out-of-bounds Read
Published
2026-04-03T20:16Z
Affected products (11)
ProductVersionsFixed in
linux/linux_kernel≥ 2.6.17, < 5.10.2535.10.253
linux/linux_kernel≥ 5.11, < 5.15.2035.15.203
linux/linux_kernel≥ 5.16, < 6.1.1676.1.167
linux/linux_kernel≥ 6.2, < 6.6.1306.6.130
linux/linux_kernel≥ 6.7, < 6.12.786.12.78
linux/linux_kernel≥ 6.13, < 6.18.206.18.20
linux/linux_kernel≥ 6.19, < 6.19.106.19.10
linux/linux_kernelall versions—
linux/linux_kernelall versions—
linux/linux_kernelall versions—
linux/linux_kernelall versions—
References (11)
EPSS history
Timeline
  • 03 APR 15:15Z
    netfilter: nf_conntrack_h323: check for zero length in DecodeQ931()
    cvelistv5