OpenClaw has a Web Fetch DoS via unbounded response parsing

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

6.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

EPSS

• CVE-2026-28394: 0.46% estimated exploitation activity in the next 30 days; percentile 40.11 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

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. 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 webfetch) 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 openclaw@2026.2.15 is published, publish this advisory without further edits. Thanks…

Published by the source

19 Feb 2026, 19:40 UTC

Last modified by the source

5 Mar 2026, 22:11 UTC

Source last checked

26 Oct 2026, 12:42 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-p536-vvpp-9mc8

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-p536-vvpp-9mc8

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# Patch Next advisory brief: CVE-2026-28394

Advisory: OpenClaw has a Web Fetch DoS via unbounded response parsing
IDs: CVE-2026-28394, GHSA-p536-vvpp-9mc8
Record: https://patchnext.com/advisories/cve-2026-28394 (revision 2, source checked 26 Oct 2026, 12:42 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: openclaw 2026.2.15. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm openclaw: affected < 2026.2.15; fixed in 2026.2.15

## Suggested inspection (read-only)
- `npm ls openclaw --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on openclaw.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-p536-vvpp-9mc8 (OSV record GHSA-p536-vvpp-9mc8 lists affected ranges: npm openclaw >=0 <2026.2.15 (fixed))
- Verified: https://github.com/advisories/GHSA-p536-vvpp-9mc8 (GitHub-reviewed advisory GHSA-p536-vvpp-9mc8 lists affected ranges: npm openclaw >=0 <2026.2.15)

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