XSS in Emby

CVE-2025-64325

Emby Server is a personal media server. Prior to version 4.8.1.0 and prior to Beta version 4.9.0.0-beta, a malicious user can send an authentication request with a manipulated X-Emby-Client value, which gets added to the devices section of the admin dashboard without sanitization. This issue has been patched in version 4.8.1.0 and Beta version 4.9.0.0-beta.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.0 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.004 (33.7th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 34th percentile — 33.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-64325: held from 0.004 to 0.004.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-64325?
CVE-2025-64325 is a critical-severity vulnerability in Emby, classified under Cross-site Scripting. CVSS score: 9.0/10. Published 2025-11-18.
How severe is CVE-2025-64325?
Critical severity. CVSS v3 base score is 9.0 out of 10.