CVE-2026-72538: PrefectHQ Prefect - Argument Injection

An argument injection vulnerability in PrefectHQ Prefect through 3.8.2 allows authenticated users to achieve remote code execution via the gitclone pull step branch field. The branch parameter is passed directly to git pull without sanitization, enabling injection of arbitrary git arguments. This represents a distinct code path from the incomplete fix applied for CVE-2026-5366 and allows command execution on the Prefect server.