CVE-2026-42423
Published: 28 April 2026
Summary
CVE-2026-42423 is a high-severity Failing Open (CWE-636) vulnerability in Openclaw Openclaw. Its CVSS base score is 7.7 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 17.4th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified are NIST 800-53 SC-24 (Fail in Known State) and SI-2 (Flaw Remediation).
Deeper analysis
CVE-2026-42423 affects OpenClaw versions prior to 2026.4.8 and involves an approval-timeout fallback mechanism that bypasses the strictInlineEval explicit-approval requirements on gateway and node exec hosts. This vulnerability, classified under CWE-636 (Not Failing Securely), allows attackers to execute inline eval commands that are intended to require explicit user approval, thereby circumventing the designed security boundary. The issue received a CVSS v3.1 base score of 7.5 (AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H) and was published on 2026-04-28.
Attackers with low privileges (PR:L) can exploit this vulnerability over the network (AV:N), though it requires high attack complexity (AC:H) and no user interaction (UI:N). Successful exploitation enables high-impact confidentiality, integrity, and availability compromises (C:H/I:H/A:H) within the unchanged scope (S:U), specifically by leveraging the timeout fallback to run unauthorized inline eval commands on affected hosts.
Mitigation is addressed in OpenClaw 2026.4.8, with a fixing commit available at https://github.com/openclaw/openclaw/commit/d7c3210cd6f5fdfdc1beff4c9541673e814354d5. Additional details are provided in the GitHub security advisory at https://github.com/openclaw/openclaw/security/advisories/GHSA-q2gc-xjqw-qp89 and the VulnCheck advisory at https://www.vulncheck.com/advisories/openclaw-strictinlineeval-approval-boundary-bypass-via-approval-timeout-fallback.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-26126
Vulnerability details
OpenClaw before 2026.4.8 contains an approval-timeout fallback mechanism that bypasses strictInlineEval explicit-approval requirements on gateway and node exec hosts. Attackers can exploit this timeout fallback to execute inline eval commands that should require explicit user approval, circumventing the intended security…
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- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
The vulnerability bypasses explicit approval for inline eval commands on network-accessible gateway and node exec hosts, directly enabling exploitation of a public-facing application (T1190) to achieve unauthorized command/script execution (T1059).
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Requires timely identification, reporting, and correction of software flaws like the approval-timeout fallback bypass in OpenClaw prior to 2026.4.8, preventing unauthorized inline eval execution.
Mandates failure to a secure state upon errors such as timeouts, directly countering the insecure fallback that bypasses strictInlineEval explicit-approval requirements.
Enforces least privilege to restrict the impact of low-privilege (PR:L) attackers exploiting the timeout fallback for unauthorized inline eval commands on gateway and node hosts.