CVE-2026-63550

The MMS BER decoder contains a boundary-handling flaw in the processing of certain fields within confirmed-request messages. When a crafted BER-encoded element is received over an established MMS session (TCP port 102), the decoder may advance its internal read position incorrectly, leading to a heap out-of-bounds read. This condition causes the MMS handling process to terminate unexpectedly, resulting in a denial-of-service.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

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 : 2026-09-03 18:07

NVD link : CVE-2026-63550

Mitre link : CVE-2026-63550

CVE.ORG link : CVE-2026-63550

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

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