CVE-2025-2019
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary code by tricking users into opening malicious VC6 files in Ashlar-Vellum Cobalt software. The heap-based buffer overflow occurs during file parsing due to insufficient length validation. Users of affected Ashlar-Vellum Cobalt installations are at risk.
💻 Affected Systems
- Ashlar-Vellum Cobalt
📦 What is this software?
Cobalt by Ashlar
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with attacker gaining the same privileges as the user running Cobalt, potentially leading to data theft, ransomware deployment, or lateral movement.
Likely Case
Attacker executes code in the context of the current user, potentially stealing sensitive files, installing malware, or establishing persistence.
If Mitigated
Limited impact if user runs with minimal privileges, application sandboxing is enabled, and malicious files are blocked at perimeter.
🎯 Exploit Status
Exploitation requires user interaction (opening malicious file) but buffer overflow to RCE is well-understood attack pattern.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Ashlar-Vellum advisory for specific patched version
Vendor Advisory: https://www.ashlar.com/security (check for CVE-2025-2019 advisory)
Restart Required: No
Instructions:
1. Check Ashlar-Vellum security advisory for CVE-2025-2019. 2. Download and install the latest Cobalt update from official vendor channels. 3. Verify installation completes successfully.
🔧 Temporary Workarounds
Block VC6 files at perimeter
allPrevent VC6 files from entering the network via email gateways, web filters, or endpoint protection.
User education and file restrictions
allTrain users not to open VC6 files from untrusted sources and implement application control to restrict VC6 file execution.
🧯 If You Can't Patch
- Run Cobalt with minimal user privileges (not as administrator)
- Implement application sandboxing or virtualization for Cobalt usage
🔍 How to Verify
Check if Vulnerable:
Check Cobalt version against vendor's patched version list for CVE-2025-2019Check Version:
Open Cobalt → Help → About (or check program properties)Verify Fix Applied:
Verify installed version matches or exceeds patched version specified in vendor advisory📡 Detection & Monitoring
Log Indicators:
- Cobalt crash logs with memory access violations
- Unexpected child processes spawned from cobalt.exe
Network Indicators:
- Downloads of VC6 files from suspicious sources
- Outbound connections from Cobalt to unknown IPs post-file-open
SIEM Query:
Process creation where parent_process contains 'cobalt' AND (process_name contains 'cmd' OR process_name contains 'powershell' OR process_name contains 'rundll32')