CVE-2026-43984Public exploitNetwork attack vector

Administrator-session script execution via unescaped log rendering

Published Jun 4, 2026 · Updated Jun 4, 2026

Stored XSS in Tautulli before 2.17.1 allows remote authenticated users to execute JavaScript in an administrator's browser. The log_js_errors endpoint writes its message parameter directly to tautulli.log, and logFile returns that file inside a pre element without escaping. Guest access or another non-admin account permits injection, but execution requires an administrator to open the affected log in the administrative viewer.

CVSS severity8.9
High
EPSS probability0.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Stored XSS in Tautulli before 2.17.1 allows remote authenticated users to execute JavaScript in an administrator's browser. The log_js_errors endpoint writes its message parameter directly to tautulli.log, and logFile returns that file inside a pre element without escaping. Guest access or another non-admin account permits injection, but execution requires an administrator to open the affected log in the administrative viewer.

The record

CVE
CVE-2026-43984
Published
Jun 4, 2026
Updated
Jun 4, 2026
Vendor
Tautulli
Product
Tautulli
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 4, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 4, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 2.17.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Tautulli · Tautulliversion=< 2.17.1

Published CVSS scores

8.9GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059.007Command and Scripting Interpreter: JavaScript/JScript

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo