CVE-2025-11464: Ashlar-Vellum Cobalt · Heap-based Buffer Overflow
Affects Ashlar-Vellum CobaltSource CVE Database V5
Not known to be exploited · CVSS 7.8 High.
Data as of 26 Oct 2026, 06:26 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 10% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 29 Oct 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-26.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Ashlar-Vellum Cobalt | Affected
| Fixed in– |
AI-suggested
Organizations should implement strict controls on file handling, including disabling automatic opening of CO files from untrusted sources and educating users about the risks of opening unsolicited files. Network-level defenses such as email filtering and sandboxing of attachments can reduce exposure. Until a vendor patch is released, consider isolating Ashlar-Vellum Cobalt installations in segmented environments with limited internet access. Employ application whitelisting and endpoint detection and response (EDR) tools to monitor for anomalous behavior indicative of exploitation attempts. Regular backups and incident response plans should be updated to address potential compromise scenarios. Engage with the vendor for timely patch deployment once available and monitor threat intelligence feeds for emerging exploit activity.
Description
Ashlar-Vellum Cobalt CO 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 CO 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-26628.