Description
Ashlar-Vellum Cobalt CO File Parsing Use-After-Free 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 CO files. The issue results from the lack of validating the existence of an object prior to performing operations on the object. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-26631.
Affected products
ashlar: cobalt
References1
- www.zerodayinitiative.com/advisories/ZDI-25-956/ Third Party Advisory
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 12 · as of 10 November 2026
- CWE
- CWE-416
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