Affected: OpenClaw

OpenClaw before 2026.4.22 contains a time-of-check/time-of-use race condition in OpenShell sandbox filesystem writes that allows attackers to redirect writes outside the intended mount root. Attackers can exploit symlink swaps during filesystem operations to bypass sandbox restrictions and write files outside the local mount root.

Affected: npm: openclaw

## Summary OpenShell FS bridge writes stay pinned to the sandbox mount root

## Affected Packages / Versions - Package: openclaw (npm) - Affected versions: <= 2026.4.21 - Fixed version: 2026.4.22

## Impact A time-of-check/time-of-use race around OpenShell sandbox filesystem writes could let a symlink swap redirect a write outside the intended local mount root.

## Fix OpenShell write paths now validate the canonical target against the mount root, reject unsafe symlink parents and symlink leaves for writes, and use root-scoped write helpers before syncing to the remote sandbox.

## Fix Commit(s) - 7be82d4fd1193bcb7e44ee38838f00bf924ffa76

## Verification - The fix commit is contained in the public v2026.4.22 tag. - openclaw@2026.4.22 is published on npm and the compiled package contains the fix. - Focused regression coverage for this path passed before publication.

Thanks @VladimirEliTokarev for reporting.