• Attackers are actively exploiting the Plex2Shell vulnerability chain to compromise internet-exposed NAS devices
  • QNAP urges immediate updates, as older Plex Media Server versions allow remote code execution and full device takeover
  • Systems exposed before patching may already be compromised and require credential resets and full remediation

QNAP has issued a security advisory warning users to install the latest version of the Plex Media Server app on their Network Attached Storage (NAS) devices.

It says older versions are being actively abused in the wild using the dreaded Plex2Shell vulnerability chain.

“Plex has confirmed that these vulnerabilities are being actively and widely exploited,” the company said in the advisory. “QNAP urges all users running Plex Media Server on a QNAP NAS to update immediately and to review their devices as described below.

What is a QNAP NAS and what does it have to do with a flaw in Plex?

A Network Attached Storage device is a dedicated system allowing users to store, back up, and share files across a network. Essentially it’s a series of hard drives connected to a local network for easy access. Consumers and businesses alike often use it as an alternative to subscription-based cloud storage models, and sometimes even to stream audio and video files.

One popular way to do that is via a software application called Plex Media Server, which allows users to organize and stream their personal collection of movies, TV shows, music, and other multimedia content. By installing Plex on their NAS, and a compatible player app on a smartphone and similar device, users can access their media libraries over a local network or remotely via the internet.

This last part - via the internet - is where trouble was recently found.

Earlier in November 2026, Plex disclosed having fixed four vulnerabilities in Media Server versions 1.43.2 and older: CVE-2026-96652, CVE-2026-96654, CVE-2026-96655, and CVE-2026-96656. Separately, these four are relatively dangerous. Chained together, they allow unauthenticated threat actors to execute arbitrary code with the highest privileges, remotely. In other words, they can use Plex Media Server to take over the QNAP NAS and, if they choose to, access and steal sensitive content found there. These four have been given the nickname Plex2Shell.

Plex released a fix in September 2026, and a proof-of-concept (PoC) exploit was made available a few weeks later. Since then, multiple security companies reported seeing Plex2Shell abused in the wild, mostly to install proxy software and cryptocurrency miners. The latter might not be particularly useful, given that most miners require powerful GPU units, but the former could prove lucrative.

Patching Plex

A proxy network allows cybercriminals to route their traffic through legitimate residential infrastructure, helping them not just to hide their identities and whereabouts, but also to launch disruptive Distributed Denial of Service (DDoS) attacks. As such, residential proxy services are always in demand, and can earn their operators a hefty sum.

The US Cybersecurity and Infrastructure Security Agency (CISA) added all four bugs to its Known Exploited Vulnerabilities (KEV) catalog on October 20, and gave Federal Civilian Executive Branch (FCEB) agencies a mere three-day window to apply the fix or stop using Plex entirely.

That being said, Plex addressed the flaws in Media Server version 1.43.3 (build 1.43.3.10861), which can now be downloaded via QNAP’s App center. The company confirmed that the bugs exist only in Plex Media Server, QTS and QuTS operating systems were not affected. Still, Plex said if the NAS device was reachable from the internet while running older versions of the software, updating is not enough and the NAS should be treated as compromised.

Those users are advised to complete a clean reinstall, compromise check, and credential reset.

The exact number of internet-accessible QNAP NAS devices is difficult to determine, but according to figures from BitSight, there are tens of thousands of them, right now. That does not mean all of them are vulnerable (many might not be running Plex Media Server to begin with), but the theoretical attack surface is quite large.

Via BleepingComputer