obsidian-tc HTTP transport lacks Origin/DNS-rebinding protection, enabling drive-by vault access on loopback

### Impact The Streamable HTTP transport was constructed without `enableDnsRebindingProtection`/`allowedHosts`/`allowedOrigins` and performed no `Origin`-header validation. With the documented `auth.mode: "none"` loopback default, a **drive-by web page could `POST http://127.0.0.1/mcp`** and receive caller `http-local` with scopes `["*"]` — full vault read/write — via DNS rebinding / a forged Origin. ### Patches Fixed in **1.3.1**. Upgrade to `>= 1.3.1`. The transport now enables DNS-rebinding protection and allowed hosts/origins and returns HTTP 403 on an invalid Origin (per MCP 2025-11-25). ### Workarounds Do not expose the HTTP transport with `auth.mode: "none"`; require JWT auth, or bind to a non-loopback interface behind a proxy that validates `Origin`.

Source published

23 Oct 2026 18:29:02 UTC

Source modified

23 Oct 2026 18:45:08 UTC

Observed here

24 Oct 2026 13:17:17 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

Publisher rating · CRITICAL