HIGH · CVSS 8.6
ACTIVELY EXPLOITED
PATCH AVAILABLE
CVE-2026-96656: Plex Media Server External Control of File Name or Path Vulnerability
| Vendor | Plex |
|---|---|
| Product | Media Server |
| CVSS score | 8.6 · CVSS 4.0 · HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
| EPSS | 1.8% (percentile 78) |
| Actively exploited | Yes |
| Added to CISA KEV | 20 Oct 2026 |
| CISA federal deadline | 23 Oct 2026 |
| Weakness (CWE) | CWE-73 |
| NVD published | 23 Sep 2026 |
| NVD last modified | 21 Oct 2026 |
| NVD status | Analyzed |
Affected versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Plex Media Server | before 1.43.3.10861 | 1.43.3.10861 |
Required action (CISA's text)
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.
Description (NVD)
Plex Media Server before 1.43.3.10861 allows an admin user to write arbitrary files that may be executed on load. The preference TranscoderH264Options is appended verbatim to x264's option string on every transcode. At startup, all .so files are run without signature, execute bit, or symbol checks.
SOURCES
Other Plex flaws
- CVE-2026-96655: Plex Media Server Server-Side Request Forgery (SSRF) Vulnerability
- CVE-2026-96654: Plex Media Server Improper Neutralization of Encoded URI Schemes in a Web Page Vulnerability
- CVE-2026-96652: Plex Media Server Server-Side Request Forgery (SSRF) Vulnerability
- CVE-2020-5741: Plex Media Server Remote Code Execution Vulnerability
Data from NVD, CISA KEV, FIRST EPSS and vendor advisories. Updated 21 Oct 2026.