Buffer overflow in Ashlar-Vellum Cobalt
CVE-2026-19781
Ashlar-Vellum Cobalt VS 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 VS 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-28173.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.002 (14.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 14th percentile — 14.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.001
Affected products
- Ashlar-Vellum Cobalt — versions 1204.204
Weakness classification (CWE)
References
- www.zerodayinitiative.com/advisories/ZDI-26-587/ (x_research-advisory)
Frequently asked questions
- What is CVE-2026-19781?
- CVE-2026-19781 is a high-severity vulnerability in Ashlar-Vellum Cobalt, classified under Heap-based Buffer Overflow. CVSS score: 7.8/10. Published 2026-09-15.
- How severe is CVE-2026-19781?
- High severity. CVSS v3 base score is 7.8 out of 10.