CVE-2026-42437
Published: 05 May 2026
Summary
CVE-2026-42437 is a high-severity Allocation of Resources Without Limits or Throttling (CWE-770) vulnerability. Its CVSS base score is 7.5 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Application or System Exploitation (T1499.004); ranked at the 25.5th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
Threat & Defense at a Glance
Threat & Defense Details
Likely Mitigating ControlsAI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
This control implements explicit throttling on session allocation, addressing the weakness of allocating resources without limits.
Plan testing exercises resource allocation limits and throttling during simulated failures, directly addressing weaknesses that allow unbounded resource use.
Contingency plan updates ensure recovery strategies address unbounded resource allocation, making it harder for attackers to exploit lack of throttling to cause prolonged outages.
Provides continuity when unbounded resource allocation at the primary site leads to exhaustion and downtime.
Alternate services allow operations to continue when primary allocation of resources lacks limits or throttling.
Explicit planning of security-related actions requires defining limits, windows, and resource allocations, making allocation without throttling far less likely.
Measures of performance include tracking allocation behavior and throttling effectiveness, reducing the window for resource exhaustion attacks.
Imposes an inactivity-based limit on network resource allocation, throttling the number of concurrently held connections.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
The CVE describes a remotely exploitable software flaw (oversized WebSocket frame validation failure) that directly causes application-level resource exhaustion and service denial, matching T1499.004 Application or System Exploitation.
NVD Description
OpenClaw versions 2026.4.9 before 2026.4.10 contain a denial of service vulnerability in the voice-call realtime WebSocket path that accepts oversized frames without proper validation. Remote attackers can send oversized WebSocket frames to cause service unavailability for deployments exposing the webhook…
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Deeper analysisAI
CVE-2026-42437 is a denial-of-service vulnerability (CWE-770) in OpenClaw versions 2026.4.9 and earlier, prior to 2026.4.10. The flaw occurs in the voice-call realtime WebSocket path, which fails to properly validate oversized frames. This issue, published on 2026-05-05, carries a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H), highlighting its potential for high-impact availability disruption without requiring privileges or user interaction.
Remote, unauthenticated attackers can exploit the vulnerability by sending oversized WebSocket frames to the affected voice-call realtime WebSocket path. In deployments exposing this webhook path, such attacks cause service unavailability, effectively denying service to legitimate users.
Advisories recommend upgrading to OpenClaw version 2026.4.10 or later, which includes the fix via the commit at https://github.com/openclaw/openclaw/commit/afadb7dae6738819ad9c7d2597ace0516957d20e. Further details on the vulnerability and remediation are provided in the GitHub security advisory at https://github.com/openclaw/openclaw/security/advisories/GHSA-vw3h-q6xq-jjm5 and the VulnCheck advisory at https://www.vulncheck.com/advisories/openclaw-denial-of-service-via-oversized-websocket-frames-in-voice-call-realtime-path.
Details
- CWE(s)