In Jenkins 2.355 and earlier, LTS 2.332.3 and earlier, an observable timing discrepancy on the login form allows distinguishing between login attempts with an invalid username, and login attempts with a valid username and wrong password, when using the Jenkins user database security realm.
{
"cpes": [
"cpe:2.3:a:jenkins:jenkins:*:*:*:*:lts:*:*:*",
"cpe:2.3:a:jenkins:jenkins:*:*:*:*:-:*:*:*"
],
"severity": "High"
}