Description
OpenClaw versions prior to 2026.2.15 contain a denial of service vulnerability in the web_fetch tool that allows attackers to crash the Gateway process through memory exhaustion by parsing oversized or deeply nested HTML responses. Remote attackers can social-engineer users into fetching malicious URLs with pathological HTML structures to exhaust server memory and cause service unavailability.
Problem types
Allocation of Resources Without Limits or Throttling
Product status
Any version before 2026.2.15
Credits
Vincent Koc (@vincentkoc)
References
github.com/...enclaw/security/advisories/GHSA-p536-vvpp-9mc8 (GitHub Security Advisory (GHSA-p536-vvpp-9mc8))
github.com/...ommit/166cf6a3e04c7df42bea70a7ad5ce2b9df46d147 (Patch Commit)
www.vulncheck.com/...nded-response-parsing-in-web-fetch-tool (VulnCheck Advisory: OpenClaw < 2026.2.15 - Denial of Service via Unbounded Response Parsing in web_fetch Tool)