CVE-2026-66349

The MMS server connection handler contains a flaw in its processing of BER-encoded request data. When an MMS confirmed request PDU containing an extended BER tag is received over an established session, the decoder may advance its internal buffer incorrectly due to a missing bounds check. This results in a one byte heap out-of-bounds read and causes the MMS service process to terminate, leading to a denial-of-service condition.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-211-10.json
https://www.cisa.gov/news-events/ics-advisories/icsa-26-211-10

Configurations

No configuration.

History

23 Oct 2026, 23:10

Type	Values Removed	Values Added
Summary		(es) El gestor de conexión del servidor MMS contiene una falla en su procesamiento de datos de solicitud codificados en BER. Cuando se recibe una PDU de solicitud confirmada de MMS que contiene una etiqueta BER extendida a través de una sesión establecida, el decodificador puede avanzar su búfer interno incorrectamente debido a una falta de verificación de límites. Esto resulta en una lectura fuera de límites de un byte en el heap y causa la terminación del proceso del servicio MMS, lo que lleva a una condición de denegación de servicio.

Information

Published : 2026-07-30 23:16

Updated : 2026-10-23 23:10

NVD link : CVE-2026-66349

Mitre link : CVE-2026-66349

CVE.ORG link : CVE-2026-66349

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

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