Sherlock is a tool for searching social media accounts. The GitHub Actions workflow validate_modified_targets.yml contains a flaw that allows command injection when triggered by a pull_request_target event. An attacker can execute arbitrary commands on the CI runner and steal the GITHUB_TOKEN by simply opening a pull request. The token provides full access to the repository, enabling any repository action.

The vulnerability affects all releases of the Sherlock Project's Sherlock before version 0.16.1. Any contributor who can open a pull request against a repository that hosts the vulnerable workflow can trigger the injection. The affected product is Sherlock, the open‑source social‑media hunting tool hosted on github.com/sherlock‑project/sherlock.

The CVSS score of 9.3 classifies the vulnerability as critical. The EPSS score is not available, but the absence from CISA’s KEV catalog does not reduce the risk. Exploitation requires only the ability to open a pull request; no review, approval, or merge is needed. The attacker can run arbitrary commands on the CI runner, exfiltrate the repository token, and then use that token to perform any action that the token permits.