CVE-2018-19943
KEVRansomware UseQNAP NAS File Station Cross-Site Scripting Vulnerability
Description
A cross-site scripting vulnerability affecting QNAP NAS File Station could allow remote attackers to inject malicious code.
If exploited, this cross-site scripting vulnerability could allow remote attackers to inject malicious code. QNAP has already fixed these issues in the following QTS versions. QTS 4.4.2.1270 build 20200410 and later QTS 4.4.1.1261 build 20200330 and later QTS 4.3.6.1263 build 20200330 and later QTS 4.3.4.1282 build 20200408 and later QTS 4.3.3.1252 build 20200409 and later QTS 4.2.6 build 20200421 and later
CVSS 3.1 vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:HPublishedOct 28, 2020
Last modifiedAug 13, 2026
Added to KEVMay 24, 2022
Remediation dueJun 14, 2022
References
- qnap.com/zh-tw/security-advisory/qsa-20-01Vendor Advisory
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2018-19943US Government Resource
0 recent articles mention this CVE
82
Risk assessment · Critical
Actively exploited and used by ransomware crews. Patch immediately.
- Exploitation
- Confirmed in the wild (CISA KEV)
- Federal remediation deadline
- Overdue by 1595 days
- Ransomware
- Used in known ransomware campaigns
- CVSS
- 8.0 HIGH
- EPSS (30-day exploit probability)
- 22.7% · top 2% of all CVEs
- Weakness
- CWE-79
- Attack vector
- Network, remotely reachable
Recommended actions
- 1.Apply updates per vendor instructions.
- 2.Treat as emergency change: patch or isolate internet-facing instances first.
- 3.Review exposure: confirm which instances are reachable from the internet and restrict access until patched.
- 4.Hunt for compromise: review logs for the disclosure window, not just from the patch date.
- 5.Verify offline/immutable backups and segment the affected systems. This flaw is used for ransomware initial access.
Assessment is derived automatically from the live signals above; verify against your own asset inventory.