CVE-2026-42260 Open-WebSearch: SSRF in `fetchWebContent` MCP tool: bracketed IPv6 literals and non-resolving hostname check bypass `isPrivateOrLocalHostname`

Open-WebSearch is a multi-engine MCP server, CLI, and local daemon for agent web search and content retrieval. Prior to 2.1.7, isPublicHttpUrl / assertPublicHttpUrl in src/utils/urlSafety.ts do not recognize bracketed IPv6 literals and do not resolve DNS, which combine to allow non-blind SSRF wit...

open-websearch has SSRF in `fetchWebContent` MCP tool: bracketed IPv6 literals and non-resolving hostname check bypass `isPrivateOrLocalHostname`

Summary src/utils/urlSafety.ts exposes isPublicHttpUrl / assertPublicHttpUrl, used to gate the MCP fetchWebContent tool against private-network targets. The check has two defects that together allow non-blind SSRF with the response body returned to the caller: 1. Bracketed IPv6 literals are never...