CVE-2026-31831

HighPublic PoC

Published: 30 March 2026

Published

30 March 2026

Modified

02 April 2026

KEV Added

—

Patch

—

CVSS Score 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS Score 0.0008 24.0th percentile

Risk Priority 15 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-31831 is a high-severity Relative Path Traversal (CWE-23) vulnerability in Tautulli Tautulli. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 24.0th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified are NIST 800-53 AU-13 (Monitoring for Information Disclosure) and SI-10 (Information Input Validation).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190) and 2 other techniques. What defenders deploy: see the NIST 800-53 controls recommended below.

Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

SI-10 Information Input Validation good match

prevent

Requires validation of inputs to the /newsletter/image/images API endpoint to block path traversal sequences and prevent arbitrary file reads.

SI-2 Flaw Remediation good match

prevent

Mandates timely remediation of flaws like this path traversal vulnerability through patching to version 2.17.0 or later.

AU-13 Monitoring for Information Disclosure good match

detect

Enables monitoring for unauthorized information disclosure via anomalous file access patterns from path traversal exploitation attempts.

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access

Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.

attack.mitre.org →

T1005 Data from Local System Collection

Adversaries may search local system sources, such as file systems, configuration files, local databases, virtual machine files, or process memory, to find files of interest and sensitive data prior to Exfiltration.

attack.mitre.org →

T1083 File and Directory Discovery Discovery

Adversaries may enumerate files and directories or may search in specific locations of a host or network share for certain information within a file system.

attack.mitre.org →

Why these techniques?

Path traversal in public-facing Tautulli web endpoint directly enables remote unauthenticated file read (T1190 initial access via public app exploit; T1005 data collection from local filesystem; T1083 file/directory discovery via arbitrary path access).

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

NVD Description

Tautulli is a Python based monitoring and tracking tool for Plex Media Server. Prior to version 2.17.0, the /newsletter/image/images API endpoint is vulnerable to path traversal, allowing unauthenticated attackers to read arbitrary files from the application server's filesystem. This issue…

has been patched in version 2.17.0.

Deeper analysisAI

CVE-2026-31831 is a path traversal vulnerability (CWE-23) in Tautulli, a Python-based monitoring and tracking tool for Plex Media Server. The issue affects versions prior to 2.17.0 and is present in the /newsletter/image/images API endpoint, which enables unauthenticated attackers to read arbitrary files from the application server's filesystem. The vulnerability carries a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N) and was published on 2026-03-30.

Unauthenticated remote attackers can exploit this vulnerability over the network with low attack complexity and no user interaction required. Successful exploitation allows attackers to access and disclose arbitrary files on the server's filesystem, potentially exposing sensitive configuration data or other server-hosted information, though it does not impact integrity or availability.

The vulnerability has been patched in Tautulli version 2.17.0. Official mitigation guidance is available in the GitHub security advisory GHSA-xp55-2pf4-fv8m and the release notes for v2.17.0, recommending immediate upgrades to the fixed version.