This advisory has been withdrawn because it is a duplicate of GHSA-rwj8-pgh3-r573. This link is maintained to preserve external references.

GitPython before 3.1.52 is vulnerable to environment-variable exfiltration in Repo.clone from(). The caller-supplied remote URL is passed through Git.polish url(), which on non-Cygwin platforms calls os.path.expandvars() on the URL before invoking git clone. An attacker who controls the clone URL can embed $NAME or ${NAME} tokens that are expanded to the values of the hosting process's environment variables (e.g., AWS SECRET ACCESS KEY or GITHUB TOKEN). The resulting URL, now containing the secret, is transmitted over the network to an attacker-controlled host during the clone attempt, disclosing the secret.