What is CVE-2026-40534?

CVE-2026-40534 is a medium-severity vulnerability in Synology Diskstation Manager (Dsm), classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-09-18.

How severe is CVE-2026-40534?

Medium severity. CVSS v3 base score is 5.4 out of 10.

XSS in Synology Diskstation Manager (Dsm)

CVE-2026-40534

An improper neutralization of input during web page generation ('cross-site scripting') vulnerability in Video API in Synology DiskStation Manager (DSM) before 7.2.1-69057-10, 7.2.2-72806-7 and 7.3.2-86009-2 allows remote authenticated users to read or write limited files when the player is launched.

Vulnerability class: XSS (Cross-Site Scripting)

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.

Affected products

Synology Diskstation Manager (Dsm)

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

security@synology.com (vendor-advisory)

Frequently asked questions

What is CVE-2026-40534?: CVE-2026-40534 is a medium-severity vulnerability in Synology Diskstation Manager (Dsm), classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-09-18.
How severe is CVE-2026-40534?: Medium severity. CVSS v3 base score is 5.4 out of 10.