How severe is CVE-2018-19943?

CVE-2018-19943 has a CVSS 3.x base score of 8.0, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2018-19943 being actively exploited?

Yes. CVE-2018-19943 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-05-24, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2018-19943?

CVE-2018-19943 primarily affects Qnap Qts. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-19943?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2018-19943 have an EU (EUVD) identifier?

Yes. CVE-2018-19943 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2018-11614. It is also flagged as exploited in the EUVD (since 2022-05-24).

When was CVE-2018-19943 published?

CVE-2018-19943 was published on 2020-10-28 and last updated on 2026-06-17.

CVE-2018-19943

CVE-2018-19943 is a high-severity vulnerability in Qnap Qts with a CVSS 3.x base score of 8.0. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2022-05-24). The underlying weakness is classified as CWE-79.

Key facts

Severity: High (CVSS 3.x base score 8.0)
CVSS v2: 3.5
EPSS exploit prediction: 18% (97th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2022-05-24)
EU (EUVD) id: EUVD-2018-11614
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2022-05-24)
Weakness: CWE-79
Affected product: Qnap Qts
Published: 2020-10-28
Last modified: 2026-06-17

Description

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

Frequently asked questions

What is CVE-2018-19943?: 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
How severe is CVE-2018-19943?: CVE-2018-19943 has a CVSS 3.x base score of 8.0, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-19943 being actively exploited?: Yes. CVE-2018-19943 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-05-24, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2018-19943?: CVE-2018-19943 primarily affects Qnap Qts. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-19943?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2018-19943 have an EU (EUVD) identifier?: Yes. CVE-2018-19943 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2018-11614. It is also flagged as exploited in the EUVD (since 2022-05-24).
When was CVE-2018-19943 published?: CVE-2018-19943 was published on 2020-10-28 and last updated on 2026-06-17.

References

Affected products (11)

cpe:2.3:o:qnap:qts:*:*:*:*:*:*:*:*
cpe:2.3:o:qnap:qts:4.2.6:-:*:*:*:*:*:*
cpe:2.3:o:qnap:qts:4.2.6:build_20170517:*:*:*:*:*:*
cpe:2.3:o:qnap:qts:4.2.6:build_20190322:*:*:*:*:*:*
cpe:2.3:o:qnap:qts:4.2.6:build_20190730:*:*:*:*:*:*
cpe:2.3:o:qnap:qts:4.2.6:build_20190921:*:*:*:*:*:*
cpe:2.3:o:qnap:qts:4.2.6:build_20191107:*:*:*:*:*:*
cpe:2.3:o:qnap:qts:4.2.6:build_20200109:*:*:*:*:*:*
cpe:2.3:o:qnap:qts:4.2.6:build_20200421:*:*:*:*:*:*
cpe:2.3:o:qnap:qts:4.2.6:build_20200611:*:*:*:*:*:*
cpe:2.3:o:qnap:qts:4.2.6:build_20200821:*:*:*:*:*:*

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