CVE-2026-100558 (GCVE-0-2026-100558)

Vulnerability from cvelistv5 – Published: 2026-09-26 02:18 – Updated: 2026-09-26 02:18
VLAI
Title
OpenClaw before 2026.8.1 Resource Exhaustion via WebSocket Upgrade
Summary
OpenClaw versions before 2026.8.1 contain a resource exhaustion vulnerability in the Gateway listener that allows unauthenticated clients to retain response sockets by sending WebSocket upgrade requests without matching connection semantics. Attackers can repeatedly send malformed upgrade requests to exhaust listener resources and cause denial of service without consuming the WebSocket pre-auth connection budget.
Severity
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-400 - Uncontrolled Resource Consumption
Assigner
References
Impacted products
Vendor Product Version CPE status
OpenClaw OpenClaw Affected: 0 , < 2026.8.1 (semver)
Unaffected: 2026.8.1 (semver)
    cpe:2.3:a:openclaw:openclaw:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-09-11 00:00
Credits
BrandonChoKR
Show details on NVD website
To clipboard 

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}



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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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