AI agent vulnerability · OpenClaw

CVE-2026-28394: OpenClaw has a Web Fetch DoS via unbounded response parsing

mediumCVSS 3.1 6.5GHSA-p536-vvpp-9mc8

Summary The webfetch tool could be used to crash the OpenClaw Gateway process (OOM / resource exhaustion) by fetching and attempting to parse attacker-controlled web pages with oversized response bodies or pathological HTML nesting.

Published Feb 19, 2026 · Updated Mar 5, 2026

Affected packages

openclaw

Ecosystem: npm
Affected: < 2026.2.15
Fixed in: 2026.2.15
Check: npm ls openclaw

Advisory details

From the GitHub Advisory Database (CC BY 4.0).

Summary

The web_fetch tool could be used to crash the OpenClaw Gateway process (OOM / resource exhaustion) by fetching and attempting to parse attacker-controlled web pages with oversized response bodies or pathological HTML nesting.

Affected Packages / Versions

Package: openclaw (npm)
Affected versions: <= 2026.2.14
Fixed versions: >= 2026.2.15

Impact

An attacker can social-engineer a user (or any automation that uses web_fetch) into fetching a malicious URL that returns extremely large or deeply nested HTML. The Gateway may exhaust memory or become unresponsive, causing a denial of service.

Fix

The Gateway now caps the downloaded response body size before any HTML parsing and adds additional guards to avoid running Readability/DOM parsing on pathological HTML.

Fix Commit(s)

166cf6a3e04c7df42bea70a7ad5ce2b9df46d147

Release Process Note

This advisory is prepared for the next npm release. Once [email protected] is published, publish this advisory without further edits.

Thanks @xuemian168 for reporting.

Credited to xuemian168, ShangzhiXu.

References

How this page is made: the data panel comes from the GitHub Advisory Database, CISA’s KEV catalog, the NVD and FIRST EPSS, and updates twice a day. No analysis has been written for this entry yet. Methodology

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