GitLab has remediated an issue in GitLab CE/EE affecting all versions from 18.3 before 19.3.6, 19.4 before 19.4.3, and 19.5 before 19.5.1 that, under certain conditions, an unauthenticated user could have poisoned a shared cache's OAuth/OIDC discovery document to redirect certain flows to an externally controlled server, due to improper trust of user-supplied values when constructing endpoint URLs in cached discovery responses.
{
"cpes": [
"cpe:2.3:a:gitlab:gitlab:*:*:*:*:*:*:*:*",
"cpe:2.3:a:gitlab:gitlab:*:*:*:*:enterprise:*:*:*"
],
"severity": "High"
}