GHSA-gj9q-8w99-mp8j CVE-2026-43529

OpenClaw: TOCTOU read in exec script preflight

Low npm

Severity: 0.0 / 10; Low · CVSS 4.0
Exploit chance (EPSS): 0.08%; Chance of exploitation in the next 30 days. Higher than 0.13% of scored vulnerabilities.
Known exploited: No; Not in CISA's catalog
Weakness: CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition
Fix: 2026.4.10; Upgrade openclaw to this version or later

Description

Summary

OpenClaw's exec script preflight validator previously validated and then read a script by mutable pathname. A local race could swap the path between validation and read, causing preflight analysis to inspect a different file identity than the one that passed the workspace boundary check.

Affected Packages / Versions

Package: openclaw
Ecosystem: npm
Affected versions: < 2026.4.10
Patched versions: >= 2026.4.10

Impact

The impact is limited. This was not arbitrary full-file disclosure through the preflight error path. The validator only surfaced derived preflight content, such as a matched token, a line number, or the first non-empty JavaScript line in one branch. Exploitation also required the ability to mutate the relevant workspace path during the preflight window.

Still, this was a real TOCTOU boundary bug in code that is supposed to reason about workspace-local script files before execution. A file identity that passed the initial boundary validation could differ from the identity that was later read for preflight analysis.

Technical Details

The vulnerable flow performed separate path validation and file reads in validateScriptFileForShellBleed. Because the read was path-based, an attacker with write access to the workspace path could race replacement of the target after validation but before preflight read.

Fix

PR #62333 replaced the check-then-read flow with a pinned safe-open/read path using the shared readFileWithinRoot helper. The fixed path performs boundary verification around the opened file identity and avoids relying on a mutable pathname for the final preflight read. Regression tests cover both pre-open and post-open swap windows.

Fix Commit(s)

b024fae9e5df43e9b69b2daebb72be3469d52e91 (fix(exec): replace TOCTOU check-then-read with atomic pinned-fd open in script preflight [AI])
PR: #62333

Release Process Note

The fix first shipped in v2026.4.10. Users should upgrade to openclaw 2026.4.10 or newer; the latest npm release already includes the fix.

Credits

Thanks to @kikayli for reporting this issue.

Affected versions

npm

Package	Vulnerable	Fixed in
openclaw	`< 2026.4.10`	`2026.4.10`

How to fix

Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.

openclaw npm → `2026.4.10`

npm

npm install openclaw@2026.4.10

yarn

yarn add openclaw@2026.4.10

pnpm

pnpm add openclaw@2026.4.10

Severity breakdown

CVSS 4.0 0.0

CVSS:4.0/AV:L/AC:H/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

Attack vector: Local
Attack complexity: High
Attack requirements: None
Privileges required: None
User interaction: None
Confidentiality (vulnerable system): Low
Integrity (vulnerable system): None
Availability (vulnerable system): None
Confidentiality (subsequent systems): None
Integrity (subsequent systems): None
Availability (subsequent systems): None

CVSS 3.1 2.5

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N

Attack vector: Local
Attack complexity: High
Privileges required: Low
User interaction: None
Scope: Unchanged
Confidentiality: Low
Integrity: None
Availability: None

Weakness

CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition

The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check.

How to prevent it

Implementation: The most basic advice for TOCTOU vulnerabilities is to not perform a check before the use. This does not resolve the underlying issue of the execution of a function on a resource whose state and identity cannot be assured, but it does help to limit the false sense of security given by the check.
Implementation: When the file being altered is owned by the current user and group, set the effective gid and uid to that of the current user and group when executing this statement.
Architecture and Design: Limit the interleaving of operations on files from multiple processes.
Implementation, Architecture and Design: If you cannot perform operations atomically and you must share access to the resource between multiple processes or threads, then try to limit the amount of time (CPU cycles) between the check and use of the resource. This will not fix the problem, but it could make it more difficult for an attack to succeed.
Implementation: Recheck the resource after the use call to verify that the action was taken appropriately.
Architecture and Design: Ensure that some environmental locking mechanism can be used to protect resources effectively.
Implementation: Ensure that locking occurs before the check, as opposed to afterwards, such that the resource, as checked, is the same as it is when in use.

References

Advisories

vulncheck.com/advisories/openclaw-time-of-check-time-of-use-toctou-race-condition-…

Packages

github.com/openclaw/openclaw

Timeline

Apr 16, 2026 Published
Jun 17, 2026 Last updated by the source
Nov 1, 2026 Latest EPSS score

Advisory	Severity	Why it's related
GHSA-3x84-qq85-fj65 OpenClaw: Browser CDP discovery could accept blocked WebSocket URLs	High	Also affects openclaw
GHSA-9c3v-684m-579c OpenClaw MCP SSE redirects could forward Authorization headers	Medium	Also affects openclaw
GHSA-f397-5vjw-v2c2 OpenClaw: Shell inline-command parsing could miss an allowlist check	High	Also affects openclaw
GHSA-rx78-29qr-5hq8 OpenClaw: Workspace-derived service PATH could influence trash command selection	High	Also affects openclaw
GHSA-ccwh-wwpp-6wg5 OpenClaw: Host environment sanitizer missed two Node.js control variables	High	Also affects openclaw
GHSA-985f-72mj-8gf7 OpenClaw: Tool group policy callers could accept unvalidated group IDs	Medium	Also affects openclaw
GHSA-9v8j-9c9g-w66c OpenClaw: Bootstrap token replay could widen pending pairing scopes	Medium	Also affects openclaw
GHSA-c226-q6fx-6j6c OpenClaw: macOS Swift exec allowlist missed combined POSIX inline flags	Medium	Also affects openclaw

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