CVE-2025-65085: Ashlar Argon Buffer Overflow Vulnerability

CVE-2025-65085 Overview

A Heap-based Buffer Overflow vulnerability (CWE-122) has been identified in multiple Ashlar-Vellum CAD software products. This vulnerability is present in Ashlar-Vellum Cobalt, Xenon, Argon, Lithium, and Cobalt Share versions 12.6.1204.207 and prior. Successful exploitation could allow an attacker to disclose sensitive information or execute arbitrary code on affected systems.

Critical Impact

This heap-based buffer overflow vulnerability enables potential arbitrary code execution and information disclosure on systems running vulnerable Ashlar-Vellum CAD software, putting design data and system integrity at risk.

Affected Products

• Ashlar-Vellum Cobalt (versions ≤ 12.6.1204.207)
• Ashlar-Vellum Xenon (versions ≤ 12.6.1204.207)
• Ashlar-Vellum Argon (versions ≤ 12.6.1204.207)
• Ashlar-Vellum Lithium (versions ≤ 12.6.1204.207)
• Ashlar-Vellum Cobalt Share (versions ≤ 12.6.1204.207)

Discovery Timeline

• 2025-11-25 - CVE-2025-65085 published to NVD
• 2025-11-28 - Last updated in NVD database

Technical Details for CVE-2025-65085

Vulnerability Analysis

This vulnerability is classified as a Heap-based Buffer Overflow (CWE-122), a memory corruption issue that occurs when a program writes data beyond the boundaries of an allocated heap buffer. In the context of Ashlar-Vellum's CAD software suite, this flaw enables attackers to manipulate heap memory structures, potentially leading to arbitrary code execution or unauthorized information disclosure.

The vulnerability requires local access and user interaction to exploit, meaning an attacker would typically need to convince a user to open a specially crafted file or interact with malicious content. Once triggered, the overflow can corrupt adjacent heap memory, allowing attackers to overwrite critical data structures or function pointers.

Root Cause

The root cause stems from insufficient bounds checking when processing input data within the Ashlar-Vellum applications. When the software handles certain data structures or file formats, it fails to properly validate the size of data being written to heap-allocated buffers. This allows oversized or malformed input to overflow the intended buffer boundaries, corrupting heap metadata and potentially adjacent memory regions.

Attack Vector

The attack vector is local, requiring an attacker to either have direct access to the system or deliver a malicious payload (such as a crafted CAD file) that the victim must open. The exploitation typically follows this pattern:

1. The attacker crafts a malicious file containing data designed to trigger the buffer overflow
2. The victim opens the malicious file using one of the affected Ashlar-Vellum applications
3. The application processes the malformed data and writes beyond the allocated heap buffer
4. The heap overflow corrupts memory, potentially allowing the attacker to control program execution flow
5. The attacker achieves code execution in the context of the victim's session or extracts sensitive information from memory

For detailed technical information, refer to the CISA ICS Advisory ICSA-25-329-01.

Detection Methods for CVE-2025-65085

Indicators of Compromise

• Unexpected crashes or abnormal termination of Ashlar-Vellum applications (Cobalt, Xenon, Argon, Lithium, or Cobalt Share)
• Suspicious CAD files with unusual file sizes or malformed headers appearing in project directories
• Anomalous memory allocation patterns or heap corruption errors in application logs
• Unexplained system behavior following the opening of CAD files from untrusted sources

Detection Strategies

• Deploy endpoint detection and response (EDR) solutions capable of monitoring heap memory operations and detecting buffer overflow attempts
• Implement file integrity monitoring for CAD project directories to identify potentially malicious files
• Configure application-level logging to capture processing errors and unusual file handling behavior
• Utilize memory protection technologies such as ASLR and DEP to limit exploitation success

Monitoring Recommendations

• Monitor process behavior for Ashlar-Vellum applications, particularly when processing files from external sources
• Enable Windows Event logging to capture application crash events (Event ID 1000, 1001) associated with the affected products
• Implement network monitoring to detect file transfers of suspicious CAD formats to endpoints running vulnerable software
• Review user activity logs for instances of opening files received via email or downloaded from untrusted locations

How to Mitigate CVE-2025-65085

Immediate Actions Required

• Identify all systems running Ashlar-Vellum Cobalt, Xenon, Argon, Lithium, or Cobalt Share versions 12.6.1204.207 or earlier
• Restrict opening of CAD files from untrusted or unknown sources until patches are applied
• Implement network segmentation to isolate CAD workstations from critical infrastructure
• Enable exploit protection features (ASLR, DEP, CFG) on systems running affected software

Patch Information

Organizations should consult the CISA ICS Advisory ICSA-25-329-01 for official remediation guidance and patch availability from Ashlar-Vellum. Contact Ashlar-Vellum directly for information on updated software versions that address this vulnerability.

Workarounds

• Implement strict file filtering to block potentially malicious CAD file formats at email gateways and web proxies
• Configure application whitelisting to prevent unauthorized executables from running in the context of Ashlar-Vellum processes
• Utilize sandboxing solutions to open and validate CAD files from untrusted sources before processing on production systems
• Apply the principle of least privilege to user accounts that operate CAD software, limiting potential impact of successful exploitation

# Example: Enable Windows Exploit Protection for Ashlar-Vellum applications
# Run in elevated PowerShell

# Enable DEP and ASLR for Cobalt
Set-ProcessMitigation -Name "Cobalt.exe" -Enable DEP,ForceRelocateImages

# Enable DEP and ASLR for Xenon
Set-ProcessMitigation -Name "Xenon.exe" -Enable DEP,ForceRelocateImages

# Enable DEP and ASLR for Argon
Set-ProcessMitigation -Name "Argon.exe" -Enable DEP,ForceRelocateImages

# Enable DEP and ASLR for Lithium
Set-ProcessMitigation -Name "Lithium.exe" -Enable DEP,ForceRelocateImages