CVE-2024-43801: Jellyfin is an open source self hosted media server. The Jellyfin user profile image upload accepts SVG files, allowing for a stored XSS attack agains...

Description

Jellyfin is an open source self hosted media server. The Jellyfin user profile image upload accepts SVG files, allowing for a stored XSS attack against an admin user via a specially crafted malicious SVG file. When viewed by an admin outside of the Jellyfin Web UI (e.g. via "view image" in a browser), this malicious SVG file could interact with the browser's LocalStorage and retrieve an AccessToken, which in turn can be used in an API call to elevate the target user to a Jellyfin administrator. The actual attack vector is unlikely to be exploited, as it requires specific actions by the administrator to view the SVG image outside of Jellyfin's WebUI, i.e. it is not a passive attack. The underlying exploit mechanism is solved by PR #12490, which forces attached images (including the potential malicious SVG) to be treated as attachments and thus downloaded by browsers, rather than viewed. This prevents exploitation of the LocalStorage of the browser. This PR has been merged and the relevant code changes are included in release version 10.9.10. All users are advised to upgrade.

Metrics

CVSS 3.1

5.4/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

EPSS Probability

0.35%

26.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-200

Affected Software

Vendor	Product	Versions
Jellyfin	Jellyfin	>= 10.8.0, <= 10.9.10

References

https://github.com/jellyfin/jellyfin/pull/12490Issue Tracking, Patch
https://github.com/jellyfin/jellyfin/security/advisories/GHSA-vcmh-9wx9-rfqhThird Party Advisory
https://happy-little-accidents.pages.dev/posts/CVE-2024-43801/

Timeline

Published: Sep 2, 2024
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2024-43801?

Jellyfin is an open source self hosted media server. The Jellyfin user profile image upload accepts SVG files, allowing for a stored XSS attack against an admin user via a specially crafted malicious SVG file. When viewed by an admin outside of the Jellyfin Web UI (e.g. via "view image" in a browser), this malicious SVG file could interact with the browser's LocalStorage and retrieve an AccessToken, which in turn can be used in an API call to elevate the target user to a Jellyfin administrator. The actual attack vector is unlikely to be exploited, as it requires specific actions by the administrator to view the SVG image outside of Jellyfin's WebUI, i.e. it is not a passive attack. The underlying exploit mechanism is solved by PR #12490, which forces attached images (including the potential malicious SVG) to be treated as attachments and thus downloaded by browsers, rather than viewed. This prevents exploitation of the LocalStorage of the browser. This PR has been merged and the relevant code changes are included in release version 10.9.10. All users are advised to upgrade.

How severe is CVE-2024-43801?

CVE-2024-43801 has a CVSS score of 5.4/10 (MEDIUM severity). The EPSS model estimates a 0.35% probability of exploitation in the next 30 days.

How do I fix CVE-2024-43801?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.