Executive brief
OpenClaw, a Node.js-based file system bridge, contains a security flaw that allows users to bypass its restricted 'sandbox' environment. By exploiting a timing issue during file operations, an attacker can write data to locations on the server that should be off-limits. This could lead to the corruption of system files or unauthorized modification of data outside the application's designated storage area.
Technical details
A Time-of-Check Time-of-Use (TOCTOU) race condition exists in OpenClaw's fs-bridge component during staged write operations. While the final 'replace' step is guarded, the initial creation and population of temporary files are not pinned to a verified parent directory. An attacker with local access can exploit a race condition by changing parent-path aliases (such as symlinks) between the validation and the write steps. This allows the attacker to write arbitrary bytes to locations outside the intended sandbox mount. The vulnerability is addressed in version 2026.3.11 by ensuring all temporary file operations occur within a pinned directory context.
Affected products
- OpenClaw OpenClaw < 2026.3.11
Timeline
- 2026-03-12: advisory: GitHub Security Advisory published
- 2026-03-31: disclosed: NVD publication date
- 2026-03-11: patched: Version 2026.3.11 released