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1. EXECUTIVE SUMMARY

• CVSS v4 9.3
• ATTENTION: Exploitable remotely/low attack complexity
• Vendor: Delta Electronics
• Equipment: COMMGR
• Vulnerability: Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)

2. RISK EVALUATION

Successful exploitation of this vulnerability could allow for an attacker to remotely access the AS3000Simulator family in the COMMGR software and execute arbitrary code.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

The following versions of COMMGR, a software management platform that contain virtual PLCs, are affected:

• COMMGR (Version 1): All versions
• COMMGR (Version 2): All versions

3.2 VULNERABILITY OVERVIEW

3.2.1 USE OF CRYPTOGRAPHICALLY WEAK PSEUDO-RANDOM NUMBER GENERATOR (PRNG) CWE-338

The software uses insufficiently randomized values to generate session IDs. An attacker could easily brute force a session ID and load and execute arbitrary code.

CVE-2025-3495 has been assigned to this vulnerability. A CVSS v3.1 base score of 9.8 has been calculated; the CVSS vector string is (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).

A CVSS v4 score has also been calculated for CVE-2025-3495. A base score of 9.3 has been calculated; the CVSS vector string is (CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N).

3.3 BACKGROUND

• CRITICAL INFRASTRUCTURE SECTORS: Commercial Facilities, Communications, Critical Manufacturing, Energy, Healthcare and Public Health
• COUNTRIES/AREAS DEPLOYED: Worldwide
• COMPANY HEADQUARTERS LOCATION: Taiwan

3.4 RESEARCHER

Trend Micro's Zero Day Initiative (ZDI) reported this vulnerability to CISA.

4. MITIGATIONS

COMMGR software Version 1 has reached end of life (EOL). Delta Electronics will release a fix for COMMGR software Version 2.

Delta Electronics recommends users of COMMGR software Version 1 to take the following precautions:

• Minimize network exposure for all control system devices and software, ensuring they are not accessible from the Internet.
• When remote access is required, use secure methods such as Virtual Private Networks (VPNs).
• Place control system networks and remote devices behind firewalls and isolate them from the business network.
• Never connect programming software to any network other than the one intended for that device.

CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability.

CISA reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures.

CISA also provides a section for control systems security recommended practices on the ICS webpage on cisa.gov/ics. Several CISA products detailing cyber defense best practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies.

CISA encourages organizations to implement recommended cybersecurity strategies for proactive defense of ICS assets.

Additional mitigation guidance and recommended practices are publicly available on the ICS webpage at cisa.gov/ics in the technical information paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies.

Organizations observing suspected malicious activity should follow established internal procedures and report findings to CISA for tracking and correlation against other incidents.

No known public exploitation specifically targeting this vulnerability has been reported to CISA at this time.

5. UPDATE HISTORY

• April 15, 2025: Initial Publication