Executive brief
OpenClaw is a security analysis tool that validates shell commands before execution. A vulnerability in its command allowlist analyzer allows attackers to hide shell variable expansion within unquoted heredocs, making dangerous commands appear safe during review while executing malicious code at runtime. This could enable unauthorized data access or command execution on systems using OpenClaw for security policy enforcement.
Technical details
The vulnerability is a logic error in OpenClaw's exec command analyzer (CWE-200: information exposure). The analyzer failed to properly track shell variable expansion within unquoted heredoc bodies; specifically, it did not account for Bash's line-continuation splicing behavior where `$VAR\<newline>REST` becomes `$VARREST` inside unquoted heredocs. An attacker could craft a payload like `cat <<KEY\n$OPENAI_API_\\\nKEY` that passes allowlist review but expands to expose the full variable at runtime. No network access or authentication is required; the vulnerability exists in the static analysis phase. The fix, committed in v2026.4.22, now properly tracks heredoc bodies, rejects unquoted heredoc expansion tokens and continuation-splice bypasses, and validates quoted heredocs.
Affected products
- OpenClaw openclaw <= 2026.4.21
Timeline
- 2026-05-04: disclosed
- 2026-04-21: patched: Fix commit b2e8b7d4bb2f22eaa16f5c4b07547774e90b65a5