Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
The git hook feature in Gogs 0.5.5 through 0.12.2 allows for authenticated remote code execution. There can be a privilege escalation if access to this hook feature is granted to a user who does not have administrative privileges. NOTE: because this is mentioned in the documentation but not in the UI, it could be considered a "Product UI does not Warn User of Unsafe Actions" issue.
CWE-78 - OS Command Injection
The OS command injection weakness (also known as shell injection) is a vulnerability which enables an attacker to run arbitrary OS commands on a server. This is done by modifying the intended downstream OS command and injecting arbitrary commands, enabling the execution of unauthorized OS commands. This has the potential to fully compromise the application along with all of its data, and, if the compromised process does not follow the principle of least privileges, it may compromise other parts of the hosting infrastructure as well. This weakness is listed as number ten in the 'CWE Top 25 Most Dangerous Software Weaknesses'.