Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

webpy web.py 0.76 is vulnerable to server-side template injection (SSTI). The template engine can be tricked into executing attacker-controlled template code that built-in security checks are designed to reject. When an application precompiles templates from a directory the attacker can write to and later renders them through the precompiled template loader, the sandbox is bypassed and the attacker's code runs, resulting in arbitrary Python code execution and OS command execution on the server.