CVE-2025-41086

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.

CVSS v3.1 Score

6.5

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Weakness Type (CWE)

CWE-639 CWE-639

Affected Products

Vendor	Product	Versions
gams	gams	< 48.7.0
gams	gams	49.1.0 — 49.7.0

References

Other References

https://www.gams.com/latest/docs/RN_51.html https://www.incibe.es/en/incibe-cert/notices/aviso/authorization-bypass-gams-gams-development-corp

Frequently Asked Questions

What is CVE-2025-41086? +

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. It has a CVSS v3.1 base score of 6.5 (MEDIUM).

How severe is CVE-2025-41086? +

CVE-2025-41086 has a CVSS v3.1 score of 6.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-41086? +

CVE-2025-41086 affects products from gams, specifically: gams. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-41086? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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