An issue has been discovered in GitLab CE/EE affecting all versions before 17.10.7, 17.11 before 17.11.3, and 18.0 before 18.0.1. An attacker may be able to reveal masked or hidden CI variables (that they did not author) in the WebUI, by simply creating their own variable and observing the HTTP response.
CVE ID: CVE-2025-4979
CVSS Base Severity: MEDIUM
CVSS Base Score: 4.9
CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N
Vendor: GitLab
Product: GitLab
EPSS Score: 0.01% (probability of being exploited)
EPSS Percentile: 1.12% (scored less or equal to compared to others)
EPSS Date: 2025-06-19 (when was this score calculated)