CVE-2024-1347: 
GitLab vulnerability analysis and mitigation

A vulnerability was discovered in GitLab CE/EE affecting all versions before 16.9.6, all versions starting from 16.10 before 16.10.4, and all versions starting from 16.11 before 16.11.1. Under certain conditions, an attacker could bypass domain-based restrictions on an instance or a group through a crafted email address (GitLab Release, Red Hat Portal).

The vulnerability has been assigned a CVSS v3.1 base score of 4.3 (Medium severity) with the following vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N. The issue is classified under CWE-287 (Improper Authentication) and allows attackers to bypass domain-based restrictions through email address manipulation (Red Hat Portal).

When successfully exploited, this vulnerability allows attackers to bypass domain-based restrictions that are set on either a GitLab instance or a group level. This could potentially lead to unauthorized access to resources that should be restricted by domain-based controls (GitLab Release).

The vulnerability requires a low level of access privileges and no user interaction to exploit. The attack can be conducted remotely through the network, with low attack complexity (Red Hat Portal).

The vulnerability has been patched in GitLab versions 16.11.1, 16.10.4, and 16.9.6. Organizations are strongly recommended to upgrade their GitLab installations to one of these patched versions immediately. GitLab.com is already running the patched version (GitLab Release).

The vulnerability was responsibly disclosed through GitLab's HackerOne bug bounty program by security researcher garethheyes (GitLab Release).