DNS Rebinding Vulnerability in Anki Addon Affecting AnkiMC

CVE-2026-61546

What is CVE-2026-61546?

The AnkiMCP addon for the Anki flashcard application contains a vulnerability where DNS-rebinding protection is globally disabled prior to version 0.21.0. This flaw allows potential attackers to exploit unsecured interactions while a user runs the Anki application alongside the default local Streamable HTTP listener at 127.0.0.1:3141. By visiting a malicious webpage, an attacker could issue commands to the MCP server, enabling them to access sensitive data such as local collections. The lack of proper authentication mechanisms, like a bearer token or session secret, exposes users to unauthorized operations. Although destructive tools are concealed unless explicitly enabled, non-destructive functions still present a significant risk for users operating an unpatched earlier version.

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