MZ Automation libiec61850 up to 1.6.1 MMS Server Connection out-of-bounds

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.0$0-$5k1.29

Summaryinfo

A vulnerability marked as critical has been reported in MZ Automation libiec61850 up to 1.6.1. This affects an unknown part of the component MMS Server Connection Handler. Performing a manipulation results in out-of-bounds. This vulnerability is cataloged as CVE-2026-66349. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability, which was classified as critical, was found in MZ Automation libiec61850 up to 1.6.1. This affects an unknown code of the component MMS Server Connection Handler. The manipulation with an unknown input leads to a out-of-bounds vulnerability. CWE is classifying the issue as CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

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.

The advisory is shared at cisa.gov. This vulnerability is uniquely identified as CVE-2026-66349 since 07/27/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. Neither technical details nor an exploit are publicly available.

Upgrading to version 1.6.2 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: libiec61850 1.6.2

Timelineinfo

07/27/2026 CVE reserved
07/30/2026 +3 days VulDB entry created
07/31/2026 +0 days Advisory disclosed
07/31/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: cisa.gov
Status: Confirmed

CVE: CVE-2026-66349 (🔒)
GCVE (CVE): GCVE-0-2026-66349
GCVE (VulDB): GCVE-100-384969

Entryinfo

Created: 07/31/2026 00:56
Changes: 07/31/2026 00:56 (55)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Do you need the next level of professionalism?

Upgrade your account now!