GHSA-p536-vvpp-9mc8 — medium GitHub Advisory (CVE-2026-28394) in npm/openclaw

Description

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.

Basic information

Type: reviewed
Severity: medium
Advisory on GitHub: Open advisory ↗
Repository advisory: Open repository advisory ↗
Source code: Browse source ↗
Published (advisory): 2026-02-19 19:40:56 UTC
Updated: 2026-03-05 21:42:22 UTC
GitHub reviewed: 2026-02-19 19:40:56 UTC

Score	Percentile
0.22%	45.25%

CVSS Scores

Base score	Version	Severity	Vector
6.5	3.1	—	`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:N) No account or special rights needed—anonymous or random user is enough. User interaction (UI:R) A real person has to do something—click, install, enable—otherwise it doesn’t land. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:N) Doesn’t really leak secrets in a meaningful way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.

Identifiers

Type	Value
GHSA	GHSA-p536-vvpp-9mc8 ↗
CVE	CVE-2026-28394 ↗

CWEs

CWE id	Name
CWE-400	Uncontrolled Resource Consumption

Credits

xuemian168 (reporter)
ShangzhiXu (coordinator)

Affected packages (1)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem	Package	Vulnerable range	First patched	Vulnerable functions
npm	openclaw	< 2026.2.15	2026.2.15	—

OpenClaw has a Web Fetch DoS via unbounded response parsing