(0Day) Ashlar-Vellum Cobalt XE File Parsing Stack-based Buffer Overflow Remote Code Execution Vulnerability
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 XE files. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of the current process.
Additional Details
11/12/25 - ZDI reported the vulnerability to the vendor
11/12/25 - the vendor acknowledged the receipt of the report
03/04/26 - ZDI asked for updates
07/13/26 - ZDI asked for updates
08/06/26 - ZDI asked for updates
10/29/26 - ZDI notified the vendor of the intention to publish the case as a 0-day advisory
-- Mitigation: Given the nature of the vulnerability, the only salient mitigation strategy is to restrict interaction with the product
Disclosure Timeline
- 2025-11-11 - Vulnerability reported to vendor
- 2026-11-04 - Coordinated public release of advisory
- 2026-11-04 - Advisory Updated
Credit
Rocco Calvi (@TecR0c) with TecSecurity
