CVE-2026-48559 Lightweight Music Server 3.76.0 Stored XSS via Media File Metadata Tags
Attackers can execute arbitrary JavaScript in the web interface by embedding malicious HTML in media file metadata tags, potentially leading to account takeover.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-48559?
CVE-2026-48559 is a medium-severity cross-site scripting vulnerability in epoupon lms, published on 1 Jun 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
Lightweight Music Server (LMS) though 3.76.0 contains a stored cross-site scripting vulnerability that allows attackers to execute arbitrary JavaScript by embedding malicious HTML in media file metadata tags such as GENRE, ARTIST, or ALBUM. Attackers can introduce a crafted media file into the victim's library, causing the payload to be saved during library scanning and executed automatically in the web interface due to tag content being rendered using Wt::TextFormat::UnsafeXHTML without sanitization in src/lms/ui/Utils.cpp.
Weakness: CWE-79
Which versions are affected by CVE-2026-48559?
How do I fix CVE-2026-48559?
No fix has been published for CVE-2026-48559 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-48559 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-48559 exists.
Sources
Also known as GHSA-m7jj-hw4m-mc77.