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

No history.

Information

Published : 2026-07-30 23:16

Updated : 2026-09-08 19:30

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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