Tautulli EUVD-2026-17184

Requires high-privilege authenticated access to Tautulli prior to version 2.17.0 with ability to create or modify notification templates. Attacker must craft a malicious template using lambda expressions to bypass sandbox restrictions in str_eval() function and execute arbitrary code.

Real-world risk is moderate despite the high 7.5 CVSS score. The CVSS vector CVSS:4.0/AV:N/AC:H/PR:H reveals critical limitations: network-accessible (AV:N) but requires high privileges (PR:H, authenticated administrator access) and high attack complexity (AC:H). This significantly constrains the threat model to scenarios where an attacker has already compromised administrative credentials or represents a malicious insider. The triple-high impact ratings (VC:H/VI:H/VA:H) confirm that successful exploitation grants complete system compromise with arbitrary code execution capabilities in the Tautulli server context. No EPSS score is provided, and no public exploit identified at time of analysis, suggesting this remains a theoretical vulnerability without widespread weaponization. The absence of CISA KEV listing indicates no confirmed active exploitation in real-world environments. From an SSVC perspective, while the technical impact is total system compromise and the vulnerability is likely automatable once credentials are obtained, the high privilege requirement substantially reduces prioritization urgency compared to unauthenticated RCE vulnerabilities. Organizations should prioritize patching based on whether Tautulli administrators are considered high-trust users or potential insider threats.

An attacker with compromised Tautulli administrator credentials accesses the notification configuration interface and crafts a malicious notification template containing a lambda expression designed to bypass sandbox restrictions. For example, the attacker embeds lambda functions that access restricted Python builtins or system modules stored in nested code object constants. When Tautulli processes this template through the str_eval() function during notification triggering (such as on Plex media playback events), the sandbox inspection only examines the outer code object's co_names attribute, completely missing the malicious attribute accesses hidden within the lambda's co_consts. The sandboxed eval() executes the attacker's arbitrary Python code with the privileges of the Tautulli process, potentially enabling system command execution, credential theft from configuration files, lateral movement to the underlying Plex infrastructure, or persistent backdoor installation. The high attack complexity stems from requiring both valid admin credentials and sophisticated understanding of Python's code object structure to craft the bypass payload.