What’s Vulnerable › Vulnerabilities
CVE-2026-39991: Stored Cross-Site Scripting (XSS) in Note Station file upload functionality
- Severity: medium (CVSS 4.8 v4.0)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.3% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-10-15 · updated 2026-10-29
- Weakness: CWE-79
Description
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
Affected products
- QNAP Systems Inc. Notes Station 3: from 3.9.x before 3.9.12 — fixed in 3.9.12
How to fix
Upgrade to a fixed version: QNAP Systems Inc. Notes Station 3 3.9.12. Check the vendor advisory for mitigations.
References
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