How severe is CVE-2018-19953?

CVE-2018-19953 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2018-19953 being actively exploited?

Yes. CVE-2018-19953 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-2018-19953?

CVE-2018-19953 primarily affects Qnap Qts. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-19953?

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-2018-19953 have an EU (EUVD) identifier?

Yes. CVE-2018-19953 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2018-11624. It is also flagged as exploited in the EUVD (since 2022-05-24).

When was CVE-2018-19953 published?

CVE-2018-19953 was published on 2020-10-28 and last updated on 2026-06-17.

CVE-2018-19953

CVE-2018-19953 is a medium-severity vulnerability in Qnap Qts with a CVSS 3.x base score of 6.1. 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: Medium (CVSS 3.x base score 6.1)
CVSS v2: 4.3
EPSS exploit prediction: 24% (98th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2022-05-24)
EU (EUVD) id: EUVD-2018-11624
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 the issue in the following QTS versions. QTS 4.4.2.1231 on build 20200302; QTS 4.4.1.1201 on build 20200130; QTS 4.3.6.1218 on build 20200214; QTS 4.3.4.1190 on build 20200107; QTS 4.3.3.1161 on build 20200109; QTS 4.2.6 on build 20200109.

Frequently asked questions

What is CVE-2018-19953?: If exploited, this cross-site scripting vulnerability could allow remote attackers to inject malicious code. QNAP has already fixed the issue in the following QTS versions. QTS 4.4.2.1231 on build 20200302; QTS 4.4.1.1201 on build 20200130; QTS 4.3.6.1218 on build 20200214; QTS 4.3.4.1190 on build 20200107; QTS 4.3.3.1161 on build 20200109; QTS 4.2.6 on build 20200109.
How severe is CVE-2018-19953?: CVE-2018-19953 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2018-19953 being actively exploited?: Yes. CVE-2018-19953 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-2018-19953?: CVE-2018-19953 primarily affects Qnap Qts. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-19953?: 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-2018-19953 have an EU (EUVD) identifier?: Yes. CVE-2018-19953 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2018-11624. It is also flagged as exploited in the EUVD (since 2022-05-24).
When was CVE-2018-19953 published?: CVE-2018-19953 was published on 2020-10-28 and last updated on 2026-06-17.

References

Affected products (7)

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:*:*:*:*:*:*

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