The shell command analyzer (splitShellPipeline) skipped all token
validation while parsing heredoc bodies. When the heredoc delimiter
was unquoted, bash performs command substitution on the body content,
allowing $(cmd) and backtick expressions to execute arbitrary commands
that bypass the exec allowlist.
Track whether heredoc delimiters are quoted or unquoted. When unquoted,
scan the body for $( , ${ , and backtick tokens and reject the command.
Quoted heredocs (<<'EOF' / <<"EOF") are safe - the shell treats their
body as literal text.
Ref: https://github.com/openclaw/openclaw/security/advisories/GHSA-65rx-fvh6-r4h2
Peter Steinberger