CVE-2022-3870
Description
An issue has been discovered in GitLab CE/EE affecting all versions starting from 10.0 before 15.5.7, all versions starting from 15.6 before 15.6.4, all versions starting from 15.7 before 15.7.2. GitLab allows unauthenticated users to download user avatars using the victim's user ID, on private instances that restrict public level visibility.
Summary dbcve.org
GitLab CE/EE versions before 15.5.7, 15.6.4, and 15.7.2 contains an information disclosure vulnerability where unauthenticated users can download user avatars using the victim's user ID, even on private GitLab instances that restrict public-level visibility. This allows attackers to enumerate valid user accounts.
Mitigation
Upgrade to GitLab 15.5.7, 15.6.4, 15.7.2 or later versions. For immediate workarounds, verify that network-level restrictions are in place to limit unauthenticated access to avatar endpoints.