CVE-2026-13623 Cross-site scripting in DiskStation Manager (DSM)
Authenticated administrators can exploit XSS in Synology DSM Theme API to read or write limited files.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-13623?
CVE-2026-13623 is a medium-severity cross-site scripting vulnerability in Synology DiskStation Manager (DSM), published on 18 Sep 2026. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.
Official description
An improper neutralization of input during web page generation ('Cross-site Scripting') vulnerability in Theme API in Synology DiskStation Manager (DSM) before 7.2.1-69057-12, 7.2.2-72806-9, 7.3.2-86009-4 and 7.4-90075 allows remote authenticated users with administrator privileges to read or write limited files.
Weakness: CWE-79
Which versions are affected by CVE-2026-13623?
How do I fix CVE-2026-13623?
No fix has been published for CVE-2026-13623 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-2026-13623 being exploited?
There is no known exploitation of CVE-2026-13623 in the wild and no public exploit code.
Sources
Also known as GHSA-ch48-w544-84qr.