Tautulli up to 2.17.0 Newsletter Render Endpoint special elements used in a template engine

Summaryinfo

A vulnerability was found in Tautulli up to 2.17.0. It has been classified as critical. Affected is an unknown function of the component Newsletter Render Endpoint. The manipulation leads to improper neutralization of special elements used in a template engine. This vulnerability is referenced as CVE-2026-41065. Remote exploitation of the attack is possible. No exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Tautulli up to 2.17.0. This issue affects an unknown code block of the component Newsletter Render Endpoint. The manipulation with an unknown input leads to a improper neutralization of special elements used in a template engine vulnerability. Using CWE to declare the problem leads to CWE-1336. The product uses a template engine to insert or process externally-influenced input, but it does not neutralize or incorrectly neutralizes special elements or syntax that can be interpreted as template expressions or other code directives when processed by the engine. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Tautulli is a Python based monitoring and tracking tool for Plex Media Server. Versions prior to 2.17.1 are vulnerable to remote code execution via the newsletter custom template directory feature. On a fresh install before the setup wizard is completed, all management endpoints are completely unauthenticated. An attacker can create a newsletter agent, point the custom template directory to an attacker-controlled SMB share serving a malicious Mako template, and trigger execution via the newsletter render endpoint, all with zero credentials and no local access to the target system. On a completed install with credentials configured, the same chain is exploitable by any admin. Version 2.17.1 fixes the issue.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-41065 since 04/16/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1221 for this issue.

It is declared as proof-of-concept.

Upgrading to version 2.17.1 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-34273). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

• Tautulli

Version

• 2.0
• 2.1
• 2.2
• 2.3
• 2.4
• 2.5
• 2.6
• 2.7
• 2.8
• 2.9
• 2.10
• 2.11
• 2.12
• 2.13
• 2.14
• 2.15
• 2.16
• 2.17.0

Website

• Product: https://github.com/Tautulli/Tautulli/

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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