Live Exposure Defense: From CVE to Confirmed Exposure in 12 Hours – See more

Back
New CVE Detected

CVE-2026-100558 – Denial of Service (Resource Exhaustion) – OpenClaw before 2026.8.1

Be the first to know when new zero-days emerge:

Subscribe to Email Alerts
Subscribe to RSS Feed

Summary

CVE-2026-100558 is a resource exhaustion vulnerability (CWE-400) in the Gateway listener of OpenClaw, an npm-distributed product. Unauthenticated remote attackers can send WebSocket upgrade requests that lack matching connection semantics, causing the listener to hold open response sockets and associated request state without consuming the WebSocket pre-authentication connection budget. Repeated exploitation exhausts listener resources and causes denial of service; the flaw carries a CVSS v4.0 base score of 8.7 (High).

Technical details

  • Root cause: The Gateway listener routes HTTP requests that present a WebSocket upgrade header but lack proper connection semantics to a standard handler, which fails to properly terminate the response, leaving the socket and request state open.
  • Trigger conditions: An attacker sends malformed WebSocket upgrade requests to the Gateway listener; because these requests do not match expected connection semantics, they bypass the normal WebSocket pre-authentication connection budget that would otherwise limit resource use.
  • Attack vector: Network-based, no authentication or user interaction required, low attack complexity.
  • Impact: Exhaustion of listener resources leading to denial of service (availability impact only — no confidentiality or integrity impact).

Affected software

  • OpenClaw (npm package openclaw) — all versions prior to 2026.8.1
  • Fixed in version 2026.8.1 and later

Severity

  • CVSS v3.1: 7.5 (High) — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
  • CVSS v4.0: 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

Mitigation and recommended actions

  • Immediate: Upgrade OpenClaw to version 2026.8.1 or later, which fixes the Gateway listener’s handling of malformed upgrade requests.
  • If unable to patch immediately:
    • Restrict access to the Gateway listener to loopback-only where possible.
    • Place the Gateway behind a reverse proxy that validates WebSocket upgrade requests and enforces its own connection limits before traffic reaches OpenClaw.

References

Are you exposed?

Get a free report of your organization’s exposure to this CVE and threat

  • Mapping of all Assets with this Technology
  • Identification of potentially exposed assets to this CVE
  • Confirmation of verified exploitable assets
Get Exposure Report

How IONIX’s External Exposure Management Platform Detects and Validates
Zero-Days to Shrink MTTR

1

Map your entire attack surface (continously)

IONIX uses multi-factor discovery methods, including DNS analysis, certificate mapping, metadata inspection, and more, to automatically map every internet-facing asset across your environment. This includes cloud instances, third-party platforms, shadow IT, and even forgotten infrastructure that traditional tools miss.

2

Monitor for new CVEs

Dozens of threat intel feeds using agentic technology are continuously analyzed to detect the appearance of proof-of-concept code, exploit kits, and indicators of active targeting. IONIX goes further by applying AI to proactively evaluate whether emerging vulnerabilities are likely to be exploited, even before PoCs go public.

3

Identify Potential External Exposures

Not all CVEs matter. IONIX filters vulnerabilities by asking attacker-centric questions: Can it be reached from the internet? Does it require authentication? Is it being exploited in the wild? This dramatically reduces noise and focuses teams on threats that can actually be weaponized.

4

Create Safe, Scalable Exploit Validations

IONIX transforms real-world PoCs into safe, non-intrusive test payloads that can be run in production environments without disruption. These simulations are precisely targeted to the systems that are vulnerable, ensuring rapid validation without unnecessary load.

5

Execute Exploit Validations

By combining context about software stack, versioning, exposure status, and reachability, IONIX ensures that only the right payloads are executed against the right assets, maximizing efficiency and minimizing risk.

6

Drive Fast and Actionable Remediation

Results are routed through integrations with ticketing, SOAR, and SIEM tools. Issues are written in plain language, bundled into remediation clusters, and prioritized based on asset criticality, exploitability, and blast radius. This shortens mean time to remediation (MTTR) and empowers teams to act with confidence.

Are you exposed?

Get a free report of your organization’s exposure to this CVE and threat

  • Mapping of all Assets with this Technology
  • Identification of potentially exposed assets to this CVE
  • Confirmation of verified exploitable assets
Get Exposure Report
Close

Subscribe to Threat Center RSS

Copy/paste the link below into your preferred RSS reader or follow these instructions to subscribe to Slack alerts.

Open RSS feedSlack setup instructions

Close

Get Real-Time CVE Alerts to Your Email

Be the first to know when new zero-days emerge