{"id":"CVE-2026-61546","published":"2026-10-28T22:17:15.590","lastModified":"2026-10-28T22:17:15.590","description":"AnkiMCP is an Anki addon that implements an MCP server, enabling AI assistants to interact with the Anki flashcard application. Prior to version 0.21.0, `anki_mcp_server/mcp_server.py` globally disables FastMCP DNS-rebinding protection through `TransportSecuritySettings` with `enable_dns_rebinding_protection=False`, including for the default local Streamable HTTP listener. The defaults in `anki_mcp_server/config.py` enable `http_enabled` on `127.0.0.1:3141`, with an empty `http_path` selecting the root endpoint. No bearer token, API key, session secret, strict `Host` allowlist or strict `Origin` allowlist is enforced before `initialize`, `tools/list` and `tools/call` reach MCP dispatch. A victim who visits a malicious web page while Anki and the listener are running can have browser requests rebound to loopback, allowing the attacker to `initialize` MCP, enumerate tools, read the local collection, and perform enabled non-destructive note/deck creation or updates. The attacker needs neither LAN position nor a local process. Available operations depend on enabled tool filters; destructive tools are hidden unless `enabled_destructive_tools` is opted into, limiting deletion-level impact but not the exposed read/write operations. The reported harness confirms real MCP tool dispatch with substituted Anki bridge responses rather than demonstrating destructive changes to a real collection. Disabling protection for tunnels/proxies also disables it for the normal loopback configuration. This issue is fixed in version 0.21.0.","cvssScore":null,"cvssSeverity":null,"cvssVector":null,"cwes":["CWE-346","CWE-350"],"vendors":[],"products":[],"references":[{"url":"https://github.com/ankimcp/anki-mcp-server-addon/commit/6dcb6939b0ecc0801f45cf0d241dc946aad1654f","tags":[]},{"url":"https://github.com/ankimcp/anki-mcp-server-addon/commit/d5306ff42d68f1e3b82a96878eb059437e820316","tags":[]},{"url":"https://github.com/ankimcp/anki-mcp-server-addon/security/advisories/GHSA-j9xx-59ph-wmr6","tags":[]},{"url":"https://github.com/ankimcp/anki-mcp-server-addon/tree/v0.21.0","tags":[]}],"exploitRefs":[{"url":"https://github.com/ankimcp/anki-mcp-server-addon/commit/6dcb6939b0ecc0801f45cf0d241dc946aad1654f","tags":[]},{"url":"https://github.com/ankimcp/anki-mcp-server-addon/commit/d5306ff42d68f1e3b82a96878eb059437e820316","tags":[]},{"url":"https://github.com/ankimcp/anki-mcp-server-addon/security/advisories/GHSA-j9xx-59ph-wmr6","tags":[]},{"url":"https://github.com/ankimcp/anki-mcp-server-addon/tree/v0.21.0","tags":[]}],"hasPoc":true,"ai":null}