Anki launches a local HTTP server to serve media files and web pages for its interface. Before version 25.09.3 the server did not enforce strict origin checks, allowing any web page loaded in a browser to send GET or POST requests to the local address. A malicious website could therefore trigger side‑effecting actions or disclose media data, with the severity depending on the browser’s Private Network Access controls. The vulnerability is confined to the local machine and does not expose data to the wider network, but it permits an attacker to interact with the Anki application from an external origin.

The Anki desktop application from ankitects:anki is affected in all releases prior to 25.09.3. The issue was fixed in the 25.09.3 release.

The CVSS score of 2.1 indicates a low overall risk, and the EPSS score of <1% shows a very small chance of exploitation. The vulnerability is not listed in the CISA KEV catalog. Based on the description, it is inferred that a user who has Anki running and visits a compromised site could be used to send requests to the local server; whether the request succeeds depends on the browser’s Private Network Access restrictions.