IM
IronMonkey Threat Research

CVE-2026-23455 CRITICAL

Published: 2026-04-03 | Last Modified: 2026-07-24 | Status: Modified

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.

Additional Descriptions (1)

En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta: netfilter: nf_conntrack_h323: comprobación de longitud cero en DecodeQ931() En DecodeQ931(), la ruta de código UserUserIE lee una longitud de 16 bits del paquete, luego la decrementa en 1 para omitir el byte discriminador del protocolo antes de pasarla a DecodeH323_UserInformation(). Si la longitud codificada es 0, el decremento se ajusta a -1, que luego se pasa como un valor grande al decodificador, lo que lleva a una lectura fuera de límites. Se añade una comprobación para asegurar que 'len' sea positivo después del decremento.

CVSS Metrics

Base Score: 9.1 (CRITICAL)

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

Attack VectorNETWORK
Attack ComplexityLOW
Privileges RequiredNONE
User InteractionNONE
ScopeUNCHANGED
Confidentiality ImpactHIGH
Integrity ImpactNONE
Availability ImpactHIGH

Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Type: Secondary

Exploitability Score: 3.9

Impact Score: 5.2

Weaknesses

Source Type Description
[email protected] Primary
en CWE-125

Affected Products

Vendor Product Version Update Type
linux linux_kernel * <built-in method update of dict object at 0x7d23a5312bc0> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7d23ac6c12c0> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7d23af4b3d40> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7d23a59c9a80> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7d23a53113c0> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7d23a5311540> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7d23a5311480> Operating System
linux linux_kernel 7.0 <built-in method update of dict object at 0x7d23bea20740> Operating System
linux linux_kernel 7.0 <built-in method update of dict object at 0x7d23af70ba00> Operating System
linux linux_kernel 7.0 <built-in method update of dict object at 0x7d23a5311280> Operating System
linux linux_kernel 7.0 <built-in method update of dict object at 0x7d2364d687c0> Operating System

Affected Configurations

Operator: OR

Vulnerable CPE
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*

References

Notification
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