(0Day) Ashlar-Vellum Cobalt VC6 File Parsing Integer Overflow Remote Code Execution Vulnerability
Rocco Calvi
ZDI ID: ZDI-25-637
ZDI-CAN: ZDI-CAN-25704
- CVSS
- 7.8 AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- Affected Vendors
- Ashlar-Vellum
- Affected Products
- Cobalt
Vulnerability Details
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 an integer overflow before allocating a buffer. An attacker can leverage this vulnerability to execute code in the context of the current process.
Additional Details
Disclosure Timeline
- 2024-11-21 — Vulnerability reported to vendor
- 2025-07-22 — Coordinated public release of advisory