GitPython versions prior to 3.2.0 contain a Regular Expression Denial of Service (ReDoS) vulnerability in the Actor.name_email_regex pattern used to parse commit author and committer fields. The regex can cause catastrophic backtracking when processing a commit object with a long author or committer string containing an unterminated '<' character, leading to quadratic CPU exhaustion. This can result in denial of service conditions in any service or tool that reads commit metadata via GitPython, including CI runners and repository scanners.