CVE-2026-43984 HIGH

CVE-2026-43984: Tautulli has stored XSS in logFile via guest-controlled log_js_errors input

Vendor Tautulli
Product Tautulli
Weakness CWE-79 · XSS
Published June 4, 2026
Last update June 4, 2026

CVSS base score

8.9/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction Required
Confidentiality High
Integrity High

CVSS vector

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

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

June 4, 2026 CVE published
June 4, 2026 Record updated