OpenClaw: Sandboxed sessions_spawn(runtime="acp") bypassed sandbox inheritance and allowed host ACP initialization

Summary

Sandboxed sessions_spawn(runtime="acp") could bypass sandbox inheritance and initialize host-side ACP runtime. The fix now fail-closes ACP spawn from sandboxed requester sessions and rejects sandbox="require" for runtime="acp".

Affected Packages / Versions

• Package: openclaw (npm)
• Latest published npm version at triage time: 2026.3.1 (March 2, 2026)
• Vulnerable range: <=2026.3.1
• Patched release: 2026.3.2 (released)

Technical Details

• Root cause: runtime="subagent" enforced sandbox inheritance, while runtime="acp" did not enforce equivalent sandbox/runtime checks.
• Security impact: sandbox-boundary bypass into host-side ACP initialization.
• Fixed behavior:
  • deny ACP spawn when requester runtime is sandboxed
  • deny sessions_spawn with runtime="acp", sandbox="require"
  • align sandboxed prompt guidance to avoid advertising blocked ACP paths

Fix Commit(s)

• ac11f0af731d41743ba02d8595f4d0fe747336e3
• c703aa0fe92df9fb71cf254fc46991e05fba2114