CVE-2026-39991mediumCWE-79

CVE-2026-39991: medium-severity vulnerability in QNAP Systems Inc. Notes Station 3

Stored Cross-Site Scripting (XSS) in Note Station file upload functionality

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 4.8epss 0.3%
A cross-site scripting (XSS) vulnerability has been reported to affect Notes Station 3. If a remote attacker gains a user account, they can then exploit the vulnerability to inject malicious code. We have already fixed the vulnerability in the following version: Notes Station 3 3.9.12 and later
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
Affected products
QNAP Systems Inc. · Notes Station 3
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