CVE-2025-2020 Ashlar-Vellum Cobalt VC6 File Parsing Out-Of-Bounds Write Remote Code Execution Vulnerability

High 7.8 Published 11 Mar 2025 Updated 12 Mar 2025

Remote attackers can execute arbitrary code by tricking users into opening malicious VC6 files in Ashlar-Vellum Cobalt due to an out-of-bounds write flaw.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Local or same network only
Victim action needed: A user has to click or open something
Fix: None listed

What is CVE-2025-2020?

CVE-2025-2020 is a high-severity memory corruption vulnerability in Ashlar Cobalt, published on 11 Mar 2025. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

Official description

Ashlar-Vellum Cobalt VC6 File Parsing Out-Of-Bounds Write Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of Ashlar-Vellum Cobalt. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file.

The specific flaw exists within the parsing of VC6 files. The issue results from the lack of proper validation of user-supplied data, which can result in a write past the end of an allocated buffer. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-25254.

Weakness: CWE-787

Which versions are affected by CVE-2025-2020?

It affects 1 product.

Products include Ashlar Cobalt.

How do I fix CVE-2025-2020?

No fix has been published for CVE-2025-2020 yet. Limit exposure of the affected software until one is available.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2025-2020 being exploited?

There is no known exploitation of CVE-2025-2020 in the wild and no public exploit code.

All Ashlar Cobalt vulnerabilities

Sources

Also known as GHSA-47m3-gw83-4cqc.