CVE-2026-43984
HighCVSS 8.9Exploitation Probability (EPSS)
Low risk11th percentile - higher than 11% of all known CVEs
Summary
Tautulli is a monitoring tool for Plex Media Server. Prior to 2.17.1, the `log_js_errors` endpoint is accessible to any authenticated user, including guests. It writes attacker-controlled strings to the application log. The admin-only `logFile` view reads the log and embeds it into HTML without escaping, causing stored XSS. A guest can inject HTML/JavaScript that executes in an administrator's browser.
Risk Assessment
Risk of administrator session hijacking and malicious actions within Tautulli.
Recommendation
Update Tautulli to version 2.17.1 or later.
Other vulnerabilities in Tautulli
See all- CVE-2026-43986Critical
Tautulli versions prior to 2.17.1 expose a public `/image/<hash>` route that resolves attacker-controlled entries from `image_hash_lookup` and replays them through server-side image fetch logic. A low-privilege guest user can seed a malicious external image URL into this lookup table and trigger server-side fetches through an unauthenticated endpoint, turning an authenticated SSRF primitive into a persistent unauthenticated SSRF gadget.
- CVE-2026-43985High
Tautulli versions prior to 2.17.1 do not enforce POST method on the `configUpdate` endpoint and lack anti-CSRF tokens. An attacker can trick a logged-in administrator into visiting a malicious page that submits a cross-site request, overwriting the admin username and password, leading to administrative interface takeover.
- CVE-2026-41065High
Tautulli prior to 2.17.1 is vulnerable to remote code execution via the newsletter custom template directory feature. On a fresh install before setup wizard completion, all management endpoints are unauthenticated. An attacker can create a newsletter agent, point the template directory to a malicious SMB share with a Mako template, and trigger execution via the newsletter render endpoint.
- CVE-2026-40605Medium
Tautulli before version 2.17.1 has a path traversal vulnerability in the cache deletion endpoint. An authenticated attacker can delete directories outside the configured cache path, leading to data loss and service disruption. Fixed in version 2.17.1.
Original NVD description (English source)
Tautulli is a Python based monitoring and tracking tool for Plex Media Server. Versions prior to 2.17.1 expose `log_js_errors` to any authenticated user, including guest users when guest access is enabled. The endpoint writes attacker-controlled strings directly into the main application log. The administrator-only `logFile` view then reads that log file and embeds it into an HTML response without escaping. This creates a stored cross-site scripting condition where a low-privilege guest can inject HTML or JavaScript into the log file and have it execute in an administrator's browser when the log viewer is opened. Version 2.17.1 patches the issue.