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

8.9HIGH

Key Information:

Vendor

Tautulli

Status
Tautulli
Vendor
CVE Published:
4 June 2026

What is CVE-2026-43984?

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.

Affected Version(s)

Tautulli < 2.17.1

References

https://github.com/Tautulli/Tautulli/security/advisories/...
x_refsource_CONFIRM
https://github.com/Tautulli/Tautulli/releases/tag/v2.17.1
x_refsource_MISC

CVSS V3.1

Score:
8.9
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
Required
Scope:
Changed

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.