QTS vulnerabilities: known CVEs & security history
QNAP · Actively exploited · 14 tracked CVEs · 3 actively exploited · updated September 2026 · what is a CVE? →
This is the full list of known vulnerabilities (CVEs) across all QTS release lines — 14 in total, with 3 actively exploited in the wild. A CVE here doesn't mean your version is affected — check QTS's current status and the safe version to run.
Known QTS CVEs
Actively-exploited and most-severe first. Open any CVE for full details.
| CVE | Severity | CVSS | EPSS | Year |
|---|---|---|---|---|
| CVE-2018-19949⚡ exploited | critical | 9.8 | 24% | 2020 |
| CVE-2018-19943⚡ exploited | high | 8 | 18% | 2020 |
| CVE-2018-19953⚡ exploited | medium | 6.1 | 24% | 2020 |
| CVE-2025-66276 | critical | 9.8 | 0% | 2026 |
| CVE-2026-24719 | high | 7.2 | 1% | 2026 |
| CVE-2026-24716 | high | 7.2 | 0% | 2026 |
| CVE-2026-22893 | high | 7.2 | 1% | 2026 |
| CVE-2025-66281 | high | 7.2 | 0% | 2026 |
| CVE-2025-66280 | high | 7.2 | 0% | 2026 |
| CVE-2025-66279 | high | 7.2 | 1% | 2026 |
| CVE-2025-66273 | high | 7.2 | 1% | 2026 |
| CVE-2026-24717 | medium | 6.5 | 0% | 2026 |
| CVE-2025-62858 | medium | 6.5 | 0% | 2026 |
| CVE-2026-41539 | medium | 6.1 | 0% | 2026 |
Is my QTS version affected?
The list above spans every release. To know whether your version is affected — and the minimum safe version to upgrade to — check it directly.
Check your QTS version → · Monitor QTS for new CVEs →
QTS vulnerabilities — frequently asked
How many known vulnerabilities does QTS have?
IsItPatched tracks 14 CVEs for QTS, 3 of which are actively exploited (CISA KEV). 2 are critical-severity and 8 high-severity. These span every release line — what matters is whether the version you run is affected.
Does QTS have any actively-exploited vulnerabilities?
Yes — 3 QTS CVEs are in CISA's Known Exploited Vulnerabilities catalog, meaning they are confirmed exploited in the wild (3 linked to ransomware). Patch these as a priority.
What is the most severe QTS vulnerability?
Among tracked issues, CVE-2018-19949 (CRITICAL, CVSS 9.8), which is actively exploited, ranks highest — a Improper input validation weakness.
Is QTS safe to use?
It depends on the version. The latest supported QTS release clears the known issues; older versions may still be affected. Check the exact version you run for a verdict.
CVE data aggregated from NVD, CISA KEV and EPSS (FIRST.org). Related: QTS security status · QTS end-of-life · actively-exploited CVEs. Always verify against QNAP's advisories — see our disclaimer.