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[ CVE-2026-96655 · Published 23 Sep 2026 ]

Server-side request forgery in Plex Media Server transcoder

Exploited · CISA KEV CVSS 4.3 EPSS <1%No fix listed yet

[ Why it matters ]Priority signals

  • Exploited in the wild: on CISA's Known Exploited Vulnerabilities list since 2026-10-20

[ Analyst view ]Is this a red alert for you?

Patch within days

CISA lists it as exploited, but it needs a Plex account and its impact is limited.

Red alert if
You run an unpatched Plex Media Server with many shared users on a network that also hosts business systems.
Can wait if
You do not run Plex, or it runs on an isolated home or media network and you update it this week.
What it is
Plex Media Server before 1.43.3.10861 lets an authenticated user make the server request arbitrary internal or external addresses through the /video/:/transcode/universal path.
Impact
A user with a Plex account can use the server to reach addresses it can see, including internal systems. The direct impact is limited, but it can be used to probe the internal network.

How an attack would work MITRE ATT&CK

  1. T1078 Valid AccountsThe attacker uses a Plex user account.
  2. T1090 ProxyThe transcoder is used to send requests to other systems.
  3. T1046 Network Service DiscoveryRequests through Plex can reveal which internal services exist.

What to do

  1. Update Plex Media Server to 1.43.3.10861 or later; this fixes all four Plex flaws listed together.
  2. Review who has a shared account on your Plex server.
Written with AI from the sources on this page on 23 Oct 2026. Check the vendor's advisory before you act.

[ Description ]Official description

Plex Media Server before 1.43.3.10861 allows an authenticated user to request arbitrary internal or external addresses via the '/video/:/transcode/universal' path parameter.

CISA: Plex Media Server contains a server-side request forgery (SSRF) vulnerability that could allow an authenticated user to request arbitrary internal or external addresses via the '/video/:/transcode/universal' path parameter. This vulnerability can be chained with CVE-2026-96652, CVE-2026-96654, and CVE-2026-96656.

[ Fixes ]Fixes and patches

CISA required action (US federal deadline 3 Nov 2026): Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ References ]References