Notification template Jinja AST whitelist only inspects static Getattr nodes. Dynamic subscripts (job['job'+'_env']) and {% if job.id > 100 %} conditional gating bypass both the AST check and the test-render (stub has small job.id). At runtime, the gated branch executes and exceptions write full tracebacks into notification body, which is POSTed to attacker-controlled webhook URL. Leaks install paths, Python version, source line numbers.
Analyzing vulnerability vectors…