Plex Media Server
CVE-2026-96655
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.
What this means for your business
- It affects Plex Media Server. It matters if your company, or a supplier that handles your data, runs it.
- Attackers are already using it. CISA added it to its list of flaws used in real attacks on 20 October 2026.
- An attacker can use it remotely, over a network, with an ordinary user login, and without anyone at your company clicking anything.
- 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
- 1Check whether your company or your suppliers run Plex Media Server, and which version. The affected versions are listed further down this page.
- 2If you do, follow CISA's required action below. No patch reference has been published yet.
- 3Treat it as urgent. US federal agencies must fix it by 3 November 2026. That deadline does not apply to private companies, but it shows how seriously CISA takes it.
- 4Because attackers have used it, check the affected systems for signs of a break-in, not only for the update.
Fastnexa security experts
Attackers are already using this flaw. Is your Plex Media Server exposed?
Tell us where you run Plex Media Server and a Fastnexa penetration tester will check whether this flaw, or others like it, can be used against your websites, apps and network.
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Required action
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.
CISA’s wording, unedited. The notes it mentions are in CISA’s catalogue entry.
Scoring
- CVSS
- 4.3 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N- CVSS v4
- 5.3
- Weakness
- CWE-918
- Assigned by
- 9119a7d8-5eab-497f-8521-727c672e3725
Dates
- Published
- 2026-10-20
- Last modified
- 2026-09-29
- Added to KEV
- 2026-10-20
- Remediation due
- 2026-11-03
- Sources
- CISA KEV, NVD
Affected products
- Plex Media Server- 1.43.0.10861
As listed in the NVD configuration data. Not a statement about your estate.