CVE-2026-65421

MediumCVSS 6.5

Published: 30/07/2026(UTC)Updated: 23/10/2026(UTC)Translated: 31/07/2026(UTC)NVD NIST

Exploitation Probability (EPSS)

Low risk

0.29%

20th percentile - higher than 20% of all known CVEs

Summary

The MMS BER decoder contains a flaw in decoding fixed-width BER fields (boolean/integer): an attacker-supplied length value is not validated, causing a read past the end of a heap buffer. This leads to termination of the MMS service process and a denial-of-service condition.

Risk Assessment

An attacker can remotely crash the MMS service process, disrupting communication in power automation systems and potentially causing power supply interruptions.

Recommendation

Install the update provided by the power automation system vendor that adds length validation in the MMS BER decoder.

Other vulnerabilities in MMS BER decoder

CVE-2026-63550Medium
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.

Original NVD description (English source)

Vulnerability data from NVD (NIST) · CISA KEV · EPSS