Description
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.
References (2)
Core 2
Core References
Release Notes patch
release-notes
https://www.gams.com/latest/docs/RN_51.html
Scores
CVSS v3
6.5
EPSS
0.0003
EPSS Percentile
8.7%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-639
Status
published
Products (1)
gams/gams
< 48.7.0
Published
Dec 02, 2025
Tracked Since
Feb 18, 2026