CVSS 3.0
7.8 highCVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HCVE-2026-121743 Ashlar-Vellum Cobalt AR File Parsing Heap-based Buffer Overflow Remote Code Execution Vulnerability
High (7.8) in ashlar-vellum cobalt. EPSS 0.2% estimated probability of exploitation activity in the next 30 days.
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Ashlar-Vellum Cobalt AR File Parsing Heap-based Buffer Overflow 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 AR files. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a heap-based buffer. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-28675.
Severity
- EPSS
- 0.2% estimated probability of exploitation activity in the next 30 days; 12th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CWE
- CWE-122 Heap-based Buffer Overflow
- Published
- Modified
- Assigned by
- zdi (CNA)
- NVD analysis
- Deferred: the NVD does not plan to analyze it
- Record from
- the NVD, synced
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Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| Ashlar-Vellum Cobalt | 1204.209 |
Attack patterns (CAPEC)
- CAPEC-92 Forced Integer Overflow Likelihood: High · Severity: High
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.
History
- The NVD deferred its analysis
Changes since this site first stored the record. The same for every record: /api/public/changes.