CVE-2025-41086 Authorization bypass in GAMS from GAMS Development Corp.
Attackers can generate valid licenses to bypass usage restrictions and gain full access to GAMS commercial solvers and models.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-41086?
CVE-2025-41086 is a medium-severity authentication bypass vulnerability in GAMS, published on 2 Dec 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-639
Which versions are affected by CVE-2025-41086?
It affects 1 product.
Products include Gams Gams.
How do I fix CVE-2025-41086?
No fix has been published for CVE-2025-41086 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2025-41086 being exploited?
There is no known exploitation of CVE-2025-41086 in the wild and no public exploit code.
Sources
Also known as GHSA-ff5f-4h34-m3c8.