# Delta Electronics COMMGR weak PRNG allows remote code execution

Published: 2025-09-04 · Severity: routine · Sectors: energy, healthcare, government-national, telecommunications, manufacturing, infrastructure
Canonical: https://vorant.io/reports/437faf33-15aa-5b19-94ca-08bc9ac4101c/delta-electronics-commgr-weak-prng-allows-remote-code-execution

> Weak session ID generation in Delta COMMGR enables remote arbitrary code execution; patch to v2.10.0.

Delta Electronics COMMGR, a software management platform used to manage virtual PLCs across critical infrastructure, contains a cryptographically weak pseudo-random number generator (PRNG) used to generate session IDs. An attacker can remotely brute-force valid session IDs and gain unauthenticated access to execute arbitrary code on the system without user interaction, with a CVSS v4 score of 9.3. COMMGR Version 1 (all versions) and COMMGR Version 2 prior to v2.10.0 are affected. The vulnerability is exploitable remotely with low attack complexity and no authentication required.
Delta Electronics has released COMMGR v2.10.0 to address this issue; Version 1 has reached end-of-life and users should migrate. The vulnerability impacts critical sectors including energy, healthcare, communications, manufacturing, and government facilities worldwide. No active exploitation has been reported to CISA, but the ease of exploitation and high impact make immediate patching a priority for affected organizations.

## Mentioned in this report

- Vulnerabilities: CVE-2025-3495

## Detection guidance (public sample)

### Delta Electronics COMMGR Process Spawning Command Shell or Script Interpreter

ATT&CK: T1190

Detects a process whose parent image path contains COMMGR spawning a shell, script host, or common LOLBin, which is consistent with post-exploitation code execution after session-ID brute force against Delta Electronics COMMGR. Auto-generated starting point — validate and tune in your environment before deploying. IOC matches can false-positive on shared infrastructure and decay as adversary infrastructure rotates.

```yaml
title: Delta Electronics COMMGR Process Spawning Command Shell or Script Interpreter
description: Detects a process whose parent image path contains COMMGR spawning a
  shell, script interpreter, or common LOLBin. This is consistent with arbitrary code
  execution after an unauthenticated attacker hijacks a COMMGR session through the
  weak session-ID PRNG. Generalises on the parent/child relation, not on specific
  payloads.
tags:
- attack.initial-access
- attack.t1190
- attack.execution
logsource:
  category: process_creation
  product: windows
detection:
  selection_parent:
    ParentImage|contains: COMMGR
  selection_child:
    Image|endswith:
    - \cmd.exe
    - \powershell.exe
    - \pwsh.exe
    - \wscript.exe
    - \cscript.exe
    - \mshta.exe
    - \rundll32.exe
    - \regsvr32.exe
    - \certutil.exe
    - \bitsadmin.exe
    - \curl.exe
  condition: selection_parent and selection_child
falsepositives:
- COMMGR helper scripts or installers that legitimately launch cmd.exe during setup
  or upgrade
- Administrators running maintenance batch files through COMMGR-related tooling
level: medium
id: 7c3a9953-586d-5546-8446-9c88e0277c46
status: experimental
author: Vorant
references:
- https://www.cisa.gov/news-events/ics-advisories/icsa-25-105-07
```

Behavioural rules are generated from public reporting — validate in your environment before deploying.

Source reporting: https://www.cisa.gov/news-events/ics-advisories/icsa-25-105-07

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