For GitLab Runner before 13.0.12, 13.1.6, 13.2.3, by replacing dockerd with a malicious server, the Shared Runner is susceptible to SSRF.
Improper sanitization of branch names in GitLab Runner affecting all versions prior to 15.3.5, 15.4 prior to 15.4.4, and 15.5 prior to 15.5.2 allows a user who creates a branch with a specially crafted name and gets another user to trigger a pipeline to execute commands in the runner as that other user.
An issue has been discovered in GitLab Runner affecting all versions starting from 13.4.0 before 13.4.2, all versions starting from 13.3.0 before 13.3.7, all versions starting from 13.2.0 before 13.2.10. Insecure Runner Configuration in Kubernetes Environments
In specific circumstances, trace file buffers in GitLab Runner versions up to 14.3.4, 14.4 to 14.4.2, and 14.5 to 14.5.2 would re-use the file descriptor 0 for multiple traces and mix the output of several jobs