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OpenClaw: TOCTOU read in exec script preflight

Low severity GitHub Reviewed Published Apr 15, 2026 in openclaw/openclaw • Updated Apr 16, 2026

Package

npm openclaw (npm)

Affected versions

< 2026.4.10

Patched versions

2026.4.10

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.

References

@steipete steipete published to openclaw/openclaw Apr 15, 2026
Published to the GitHub Advisory Database Apr 16, 2026
Reviewed Apr 16, 2026
Last updated Apr 16, 2026

Severity

Low

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v4 base metrics

Exploitability Metrics
Attack Vector Local
Attack Complexity High
Attack Requirements None
Privileges Required None
User interaction None
Vulnerable System Impact Metrics
Confidentiality Low
Integrity None
Availability None
Subsequent System Impact Metrics
Confidentiality None
Integrity None
Availability None

CVSS v4 base metrics

Exploitability Metrics
Attack Vector: This metric reflects the context by which vulnerability exploitation is possible. This metric value (and consequently the resulting severity) will be larger the more remote (logically, and physically) an attacker can be in order to exploit the vulnerable system. The assumption is that the number of potential attackers for a vulnerability that could be exploited from across a network is larger than the number of potential attackers that could exploit a vulnerability requiring physical access to a device, and therefore warrants a greater severity.
Attack Complexity: This metric captures measurable actions that must be taken by the attacker to actively evade or circumvent existing built-in security-enhancing conditions in order to obtain a working exploit. These are conditions whose primary purpose is to increase security and/or increase exploit engineering complexity. A vulnerability exploitable without a target-specific variable has a lower complexity than a vulnerability that would require non-trivial customization. This metric is meant to capture security mechanisms utilized by the vulnerable system.
Attack Requirements: This metric captures the prerequisite deployment and execution conditions or variables of the vulnerable system that enable the attack. These differ from security-enhancing techniques/technologies (ref Attack Complexity) as the primary purpose of these conditions is not to explicitly mitigate attacks, but rather, emerge naturally as a consequence of the deployment and execution of the vulnerable system.
Privileges Required: This metric describes the level of privileges an attacker must possess prior to successfully exploiting the vulnerability. The method by which the attacker obtains privileged credentials prior to the attack (e.g., free trial accounts), is outside the scope of this metric. Generally, self-service provisioned accounts do not constitute a privilege requirement if the attacker can grant themselves privileges as part of the attack.
User interaction: This metric captures the requirement for a human user, other than the attacker, to participate in the successful compromise of the vulnerable system. This metric determines whether the vulnerability can be exploited solely at the will of the attacker, or whether a separate user (or user-initiated process) must participate in some manner.
Vulnerable System Impact Metrics
Confidentiality: This metric measures the impact to the confidentiality of the information managed by the VULNERABLE SYSTEM due to a successfully exploited vulnerability. Confidentiality refers to limiting information access and disclosure to only authorized users, as well as preventing access by, or disclosure to, unauthorized ones.
Integrity: This metric measures the impact to integrity of a successfully exploited vulnerability. Integrity refers to the trustworthiness and veracity of information. Integrity of the VULNERABLE SYSTEM is impacted when an attacker makes unauthorized modification of system data. Integrity is also impacted when a system user can repudiate critical actions taken in the context of the system (e.g. due to insufficient logging).
Availability: This metric measures the impact to the availability of the VULNERABLE SYSTEM resulting from a successfully exploited vulnerability. While the Confidentiality and Integrity impact metrics apply to the loss of confidentiality or integrity of data (e.g., information, files) used by the system, this metric refers to the loss of availability of the impacted system itself, such as a networked service (e.g., web, database, email). Since availability refers to the accessibility of information resources, attacks that consume network bandwidth, processor cycles, or disk space all impact the availability of a system.
Subsequent System Impact Metrics
Confidentiality: This metric measures the impact to the confidentiality of the information managed by the SUBSEQUENT SYSTEM due to a successfully exploited vulnerability. Confidentiality refers to limiting information access and disclosure to only authorized users, as well as preventing access by, or disclosure to, unauthorized ones.
Integrity: This metric measures the impact to integrity of a successfully exploited vulnerability. Integrity refers to the trustworthiness and veracity of information. Integrity of the SUBSEQUENT SYSTEM is impacted when an attacker makes unauthorized modification of system data. Integrity is also impacted when a system user can repudiate critical actions taken in the context of the system (e.g. due to insufficient logging).
Availability: This metric measures the impact to the availability of the SUBSEQUENT SYSTEM resulting from a successfully exploited vulnerability. While the Confidentiality and Integrity impact metrics apply to the loss of confidentiality or integrity of data (e.g., information, files) used by the system, this metric refers to the loss of availability of the impacted system itself, such as a networked service (e.g., web, database, email). Since availability refers to the accessibility of information resources, attacks that consume network bandwidth, processor cycles, or disk space all impact the availability of a system.
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

EPSS score

Weaknesses

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. Learn more on MITRE.

CVE ID

No known CVE

GHSA ID

GHSA-gj9q-8w99-mp8j

Source code

Credits

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