A vulnerability in GitLab CE/EE versions from 5.2 up to but not including 18.2.8, 18.3 up to 18.3.4, and 18.4 up to 18.4.2 allows an authenticated attacker to cause a denial of service by configuring malicious webhook endpoints that send crafted HTTP responses. This issue has been remediated in versions 18.2.8, 18.3.4, and 18.4.2.