OpenClaw before 2026.8.1 Resource Exhaustion via WebSocket Upgrade (CVE-2026-100558) | HOL Guard CVE

High · CVSS 8.7CVE-2026-100558

OpenClaw before 2026.8.1 Resource Exhaustion via WebSocket Upgrade

Answer in brief

CVE-2026-100558 records a High severity (CVSS 8.7) vulnerability in OpenClaw before 2026.8.1 Resource Exhaustion via WebSocket Upgrade. The current sources do not mark it as known exploited. The current feed maps OpenClaw/OpenClaw (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 26, 2026Updated Sep 26, 2026Source checked Sep 26, 2026First seen by HOL Sep 26, 2026Material review Sep 26, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 8.7
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 8.7. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps OpenClaw/OpenClaw (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
OpenClaw/OpenClawgeneric	>=0 <2026.8.1	2026.8.1

Recommended response

Check inventory. Check lockfiles and deployed manifests for OpenClaw/OpenClaw.
Review the reported fix. Update OpenClaw/OpenClaw to 2026.8.1 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 26, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 26, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 26, 2026

Sources and claim methodology

Upstream source description

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.

Quoted source text, attributed separately from HOL analysis.