Plex Media Server timeline SSRF (CVE-2026-96652)

The CVE record says an attacker using any X-Plex-Token value can include a full URL in the protocol parameter. This forces the Plex server to POST to the attacker's chosen destination. The researcher explains that the endpoint checks that a token header exists, not that it is valid. The server then builds a callback address from the unchecked parameter.

The researcher says the request comes from the server itself, from the loopback address 127.0.0.1, and that Plex trusts such requests more than outside ones. That is why this step matters: it lets an outsider reach functions meant only for the server. Plex describes the flaw as an unauthenticated server-side request forgery in the player timeline endpoint.

Our reading: the score of 4.3 counts a low privilege level, yet the text says any token value works. The real barrier is lower than the number suggests, and the number alone would put this CVE low on a patch list. CISA's catalog entry says it can be chained with CVE-2026-96654, CVE-2026-96655 and CVE-2026-96656.

Plex2Shell is the name for the chain of CVE-2026-96652, CVE-2026-96654, CVE-2026-96655 and CVE-2026-96656. CISA's entry for each one says it can be chained with the other three. The full Plex2Shell chain write-up shows where this first step leads.

In our checks on 23 October 2026, a GitHub search for this CVE id returned 5 repositories. One of them, created on 22 October, describes itself as proof of concept and verification material for this CVE. We did not run or link any of them. Our dark web and chat monitoring found 7 posts naming this CVE between 17 and 22 October, 6 on Telegram and 1 on a forum.

Plex Media Server before build 1.43.3.10861, according to the CVE record. Plex says 1.43.3.10861 and later are not affected.

Plex's post title says 1.43.2 and earlier, while its 19 October update gives the build number as the cutoff. Use the build number. The researcher's README names builds up to 1.43.3.10828 as vulnerable, so an early 1.43.3 build can still be affected.

Plex's update guide covers Windows, macOS, Linux, NAS devices and Docker. Plex says an internet-reachable server older than 1.43.3.10861 should be assumed possibly compromised.