8.7
HIGH CVSS 4.0
CVE-2026-41399
OpenClaw < 2026.3.28 - Denial of Service via Unbounded Pre-auth WebSocket Upgrades
Description

OpenClaw before 2026.3.28 accepts unbounded concurrent unauthenticated WebSocket upgrades without pre-authentication budget allocation. Unauthenticated network attackers can exhaust socket and worker capacity to disrupt WebSocket availability for legitimate clients.

INFO

Published Date :

April 28, 2026, 7:37 p.m.

Last Modified :

April 28, 2026, 8:10 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-41399 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 HIGH [email protected]
CVSS 4.0 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 HIGH [email protected]
Solution
Upgrade OpenClaw to version 2026.3.28 or later to fix WebSocket denial of service.
  • Update OpenClaw to version 2026.3.28 or newer.
  • Configure resource limits for WebSocket connections.
  • Implement pre-authentication for WebSocket upgrades.
  • Monitor system resource usage.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-41399.

URL Resource
https://github.com/openclaw/openclaw/security/advisories/GHSA-f44p-c7w9-7xr7
https://www.vulncheck.com/advisories/openclaw-denial-of-service-via-unbounded-pre-auth-websocket-upgrades
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-41399 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-41399 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-41399 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Apr. 28, 2026

    Action Type Old Value New Value
    Added Description OpenClaw before 2026.3.28 accepts unbounded concurrent unauthenticated WebSocket upgrades without pre-authentication budget allocation. Unauthenticated network attackers can exhaust socket and worker capacity to disrupt WebSocket availability for legitimate clients.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-770
    Added Reference https://github.com/openclaw/openclaw/security/advisories/GHSA-f44p-c7w9-7xr7
    Added Reference https://www.vulncheck.com/advisories/openclaw-denial-of-service-via-unbounded-pre-auth-websocket-upgrades
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.