CVE-2026-96656: Plex Media Server (High, CVSS 8.6)
- CVSS
- 8.6 High (v4.0)
- EPSS
- 0.8% chance of exploitation in the next 30 days (higher than 56.6% of CVEs)
- Exploited in the wild
- Yes, on CISA’s KEV list since Oct 20, 2026
- Public exploit
- Yes, reported in 1 GitHub repository
- Weakness
- CWE-73
- Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N- Published
- Sep 23, 2026
- CISA fix-by date
- Oct 23, 2026 (for US federal agencies)
What it is
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.
Description from the National Vulnerability Database.
What to do
CISA: 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
Check whether you run Plex Media Server, then apply the vendor’s fix or mitigation from the advisories below. Because this flaw is exploited or has public exploit code, treat it as urgent and check for signs of compromise, not just the patch level.
Advisories and fixes
ThreatRoundup coverage
Plex Servers Are Quietly Mining Crypto for Someone Else
Sources: NVD, FIRST EPSS, CISA KEV, and public exploit databases (availability only). ThreatRoundup reports whether public exploit code exists but never links to it: fake proof-of-concepts that infect security researchers are common. This page updates automatically.