CVE-2025-41086

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

V

ulnerability 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

Link	Resource
https://www.gams.com/latest/docs/RN_51.html	Release Notes
https://www.incibe.es/en/incibe-cert/notices/aviso/authorization-bypass-gams-gams-development-corp	Third Party Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:gams:gams::::::::
	cpe:2.3:a:gams:gams::::::::

History

03 Feb 2026, 17:19

Type	Values Removed	Values Added
First Time		Gams gams
CPE	cpe:2.3:a:gams:access_control_system::::::::	cpe:2.3:a:gams:gams::::::::

30 Jan 2026, 19:05

Type	Values Removed	Values Added
References	~~() https://www.gams.com/latest/docs/RN_51.html -~~	() https://www.gams.com/latest/docs/RN_51.html - Release Notes
References	~~() https://www.incibe.es/en/incibe-cert/notices/aviso/authorization-bypass-gams-gams-development-corp -~~	() https://www.incibe.es/en/incibe-cert/notices/aviso/authorization-bypass-gams-gams-development-corp - Third Party Advisory
First Time		Gams Gams access Control System
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 6.5
CPE		cpe:2.3:a:gams:access_control_system::::::::

02 Dec 2025, 14:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2025-12-02 14:16

Updated : 2026-02-03 17:19

NVD link : CVE-2025-41086

Mitre link : CVE-2025-41086

CVE.ORG link : CVE-2025-41086

JSON object : View

Products Affected

gams

CWE

CWE-639

Authorization Bypass Through User-Controlled Key

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