{"id":"CVE-2025-41086","aliases":["EUVD-2025-200244","GHSA-ff5f-4h34-m3c8"],"status":"published","title":"Authorization bypass in GAMS from GAMS Development Corp.","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.","severity":{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00229,"percentile":0.13809,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-639"],"published":"2025-12-02T13:22:23Z","modified":"2026-10-18T18:10:00Z","products":[{"vendor":"ams development corp.","product":"gams"},{"vendor":"gams","product":"gams"}],"references":[{"url":"https://www.incibe.es/en/incibe-cert/notices/aviso/authorization-bypass-gams-gams-development-corp","tags":["Third Party Advisory"]},{"url":"https://www.gams.com/latest/docs/RN_51.html","tags":["patch","release-notes","Release Notes"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-41086"},{"url":"https://github.com/advisories/GHSA-ff5f-4h34-m3c8"}],"sources":{"cve":[{"id":"CVE-2025-41086","title":"Authorization bypass in GAMS from GAMS Development Corp.","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.","status":"published","published":"2025-12-02T13:22:23.415Z","modified":"2025-12-02T14:24:21.854Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","level":"medium","assessor":"cna"}],"cwes":["CWE-639"],"updated_at":"2026-11-02T14:32:31.631102Z"}],"euvd":[{"id":"EUVD-2025-200244","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.","status":"published","published":"2025-12-02T13:22:23Z","modified":"2025-12-02T14:24:21Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"updated_at":"2026-11-02T19:49:11.096002Z"}],"ghsa":[{"id":"GHSA-ff5f-4h34-m3c8","title":"Vulnerability in the access control system of the GAMS licensing system that allows unlimited...","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.","status":"published","published":"2025-12-02T15:30:33Z","modified":"2026-01-30T21:31:22Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium"},{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-639"],"updated_at":"2026-11-02T15:05:59.660813Z"}],"nvd":[{"id":"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.","status":"published","published":"2025-12-02T14:16:25.07Z","modified":"2026-10-18T18:10:00.1Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium","assessor":"secondary"},{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-639"],"updated_at":"2026-11-02T14:11:47.746175Z"}]}}