CVE-2025-46269 is a heap-based buffer overflow vulnerability identified in multiple versions of Ashlar-Vellum's Cobalt suite, including Xenon, Argon, Lithium, and Cobalt Share, specifically versions prior to 12.6.1204.204. The vulnerability arises due to insufficient validation of user-supplied data when parsing VC6 files, a file format associated with the software. This lack of proper input validation allows an attacker to craft malicious VC6 files that, when processed by the vulnerable application, trigger a heap-based buffer overflow. Such an overflow can corrupt memory and potentially allow arbitrary code execution within the context of the current process. The CVSS 4.0 base score is 8.4, indicating a high severity level. The vector string (CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N) reveals that the attack requires local access (AV:L) and user interaction (UI:A), but no privileges or authentication are needed (PR:N, AT:N). The vulnerability impacts confidentiality, integrity, and availability at a high level, as successful exploitation can lead to full compromise of the affected application process. No known exploits are currently reported in the wild, and no patches are linked yet, indicating that mitigation may rely on vendor updates or workaround strategies. This vulnerability is classified under CWE-122, which corresponds to heap-based buffer overflows, a common and dangerous class of memory corruption bugs.

For European organizations using Ashlar-Vellum Cobalt and its related products, this vulnerability poses a significant risk. The ability to execute arbitrary code locally can lead to unauthorized access, data manipulation, or disruption of critical design and engineering workflows, as Ashlar-Vellum products are typically used in CAD and design environments. Compromise of these systems could result in intellectual property theft, sabotage of design files, or pivoting to other parts of the network. Given the local attack vector and requirement for user interaction, the threat is more pronounced in environments where untrusted files might be opened by users, such as collaborative design teams or external contractors. The lack of authentication requirements means that any local user or attacker who can trick a user into opening a malicious VC6 file could exploit this vulnerability. This could also affect organizations with remote desktop or virtual desktop infrastructure if users open malicious files in those sessions. The high impact on confidentiality, integrity, and availability underscores the criticality of addressing this vulnerability promptly to prevent potential operational disruptions and data breaches.

1. Immediate mitigation should involve restricting the opening of VC6 files from untrusted or unknown sources until a vendor patch is available. 2. Implement strict file handling policies and user training to raise awareness about the risks of opening unsolicited or suspicious VC6 files. 3. Employ application whitelisting and sandboxing techniques to isolate Ashlar-Vellum applications, limiting the scope of potential exploitation. 4. Monitor local system activity for unusual behavior indicative of exploitation attempts, such as unexpected process spawning or memory corruption alerts. 5. Coordinate with Ashlar-Vellum for timely patch deployment once available; maintain communication channels with the vendor for updates. 6. Consider deploying endpoint detection and response (EDR) solutions capable of detecting heap overflow exploitation techniques. 7. Review and tighten local user permissions to minimize the impact of a successful exploit, ensuring users operate with least privilege. 8. If possible, disable or limit features that automatically parse or preview VC6 files within the application or associated systems.