- High 8.6
- Known exploited (CISA KEV)
CVE-2026-96656
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.
Scores
The facts
- Published
- 23 September 2026
- Last changed
- 20 October 2026
- NVD status
- Modified
- Severity
- High, CVSS 8.6 out of 10 (version 4.0)
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/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… - Weakness
- Affects
- plex media server
- Known exploited
- Yes. CISA added it to the Known Exploited Vulnerabilities catalogue on 20 October 2026.
- EPSS
- 0.4% chance of exploitation activity in the next 30 days (percentile 32).
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