CVE-2026-54915
Tautulli is a Python based monitoring and tracking tool for Plex Media Server. Prior to 2.17.2, the unauthenticated /auth/redirect endpoint in plexpy/webauth.py removes forward slashes from the user-controlled redirect_uri parameter but leaves tab, line-feed, and carriage-return characters intact. With the default root HTTP_ROOT configuration, CherryPy HTTPRedirect passes the resulting value to urllib.parse.urljoin, which can resolve the whitespace-bearing path to an attacker-controlled external origin. A user who follows a crafted link can therefore be redirected outside Tautulli for phishing or post-login redirect-flow abuse, while custom non-root HTTP_ROOT configurations are not affected by this bypass. This issue is fixed in version 2.17.2.
What this means for your business
- An attacker can use it remotely, over a network, without a login, but only after tricking someone into an action such as opening a file or a link.
- FIRST's prediction model gives it a 0.2% chance of attack attempts being seen in the next 30 days, ranking above 11% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- 5.4 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N- Weakness
- CWE-601
- Assigned by
- security-advisories@github.com
Dates
- Published
- 2026-09-21
- Last modified
- 2026-09-21
- Sources
- NVD