CVE-2025-41086: Gams

Medium severity, CVSS 6.5. EPSS: 0.2% chance of exploitation in the next 30 days.

Vulnerability in the access control system of the GAMS licensing system that allows unlimited valid licenses to be generated, bypassing any usage restrictions. The validator uses an insecure checksum algorithm; knowing this algorithm and the format of the license lines, an attacker can recalculate the checksum and generate a valid license to grant themselves full privileges without credentials or access to the source code, allowing them unrestricted access to GAMS's mathematical models and commercial solvers.

Affected products

• Gams Gams: before 48.7.0 (fixed in 48.7.0); from 49.1.0, before 49.7.0 (fixed in 49.7.0)

Published 2025-12-02. Last modified 2026-06-17.