# CVE-2018-19943: QNAP NAS File Station Cross-Site Scripting Vulnerability

Source: https://junglewise.ai/threats/cve-2018-19943-qnap-nas-file-station-cross-site-scripting-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2022-05-24. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2018-19943 · Severity: critical · CVSS 8 · Exploited in the wild · Published 2022-05-24

A cross-site scripting (XSS) vulnerability in QNAP NAS File Station allows remote attackers to inject malicious code into web pages. The vulnerability requires user interaction and is known to have been exploited in the wild.

Technologies: [QNAP Network Attached Storage (NAS)](https://junglewise.ai/threats/technologies/network-attached-storage-nas). Vendors: [QNAP](https://junglewise.ai/threats/vendors/qnap).

## Quick answers

**Is CVE-2018-19943 exploited in the wild?** Yes. CVE-2018-19943 is known to be exploited in the wild, first recorded on 24 May 2022. Treat it as urgent.

**How severe is CVE-2018-19943?** Critical severity, with a CVSS score of 8, published 24 May 2022.

**Which products and versions are affected?** QNAP QTS < 4.4.2.1270 build 20200410; QNAP QTS < 4.4.1.1261 build 20200330; QNAP QTS < 4.3.6.1263 build 20200330; QNAP QTS < 4.3.4.1282 build 20200408; and 2 more.

**Is there a fix for CVE-2018-19943?** A patch was published on 2020-03-30: Earliest patch build date listed for QTS 4.4.1 and 4.3.6 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2018-19943 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2018-19943?** Check whether you run QNAP Network Attached Storage (NAS). Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Affected products

- QNAP QTS < 4.4.2.1270 build 20200410
- QNAP QTS < 4.4.1.1261 build 20200330
- QNAP QTS < 4.3.6.1263 build 20200330
- QNAP QTS < 4.3.4.1282 build 20200408
- QNAP QTS < 4.3.3.1252 build 20200409
- QNAP QTS < 4.2.6 build 20200421

## Timeline

- 2020-10-28: disclosed: NVD Published Date
- 2022-05-24: kev added: Added to CISA Known Exploited Vulnerabilities Catalog
- 2020-03-30: patched: Earliest patch build date listed for QTS 4.4.1 and 4.3.6

## Related threats

- [QNAP NAS File Station Command Injection Vulnerability](https://junglewise.ai/threats/cve-2018-19949-qnap-nas-file-station-command-injection-vulnerability)
- [QNAP NAS File Station Cross-Site Scripting Vulnerability](https://junglewise.ai/threats/cve-2018-19953-qnap-nas-file-station-cross-site-scripting-vulnerability)
- [QNAP Network-Attached Storage (NAS) Command Injection Vulnerability](https://junglewise.ai/threats/cve-2020-2509-qnap-network-attached-storage-nas-command-injection-vulnerability)
- [QNAP NAS Improper Authorization Vulnerability](https://junglewise.ai/threats/cve-2021-28799-qnap-nas-improper-authorization-vulnerability)