How severe is CVE-2021-44053?

CVE-2021-44053 has a CVSS 3.x base score of 5.7, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-44053 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-44053?

CVE-2021-44053 primarily affects Qnap Qts. In total, 15 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-44053?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-44053 published?

CVE-2021-44053 was published on 2022-05-05 and last updated on 2026-06-17.

CVE-2021-44053

CVE-2021-44053 is a medium-severity vulnerability in Qnap Qts with a CVSS 3.x base score of 5.7. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Severity: Medium (CVSS 3.x base score 5.7)
CVSS v2: 4.3
EPSS exploit prediction: 1% (49th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Qnap Qts
Published: 2022-05-05
Last modified: 2026-06-17

Description

A cross-site scripting (XSS) vulnerability has been reported to affect QNAP device running QTS, QuTS hero and QuTScloud. If exploited, this vulnerability allows remote attackers to inject malicious code. We have already fixed this vulnerability in the following versions of QTS, QuTS hero and QuTScloud: QTS 4.5.4.1991 build 20220329 and later QTS 5.0.0.1986 build 20220324 and later QuTS hero h5.0.0.1986 build 20220324 and later QuTS hero h4.5.4.1971 build 20220310 and later QuTScloud c5.0.1.1949 and later

Frequently asked questions

What is CVE-2021-44053?: A cross-site scripting (XSS) vulnerability has been reported to affect QNAP device running QTS, QuTS hero and QuTScloud. If exploited, this vulnerability allows remote attackers to inject malicious code. We have already fixed this vulnerability in the following versions of QTS, QuTS hero and QuTScloud: QTS 4.5.4.1991 build 20220329 and later QTS 5.0.0.1986 build 20220324 and later QuTS hero h5.0.0.1986 build 20220324 and later QuTS hero h4.5.4.1971 build 20220310 and later QuTScloud c5.0.1.1949 and later
How severe is CVE-2021-44053?: CVE-2021-44053 has a CVSS 3.x base score of 5.7, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-44053 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-44053?: CVE-2021-44053 primarily affects Qnap Qts. In total, 15 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-44053?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-44053 published?: CVE-2021-44053 was published on 2022-05-05 and last updated on 2026-06-17.

References

https://www.qnap.com/en/security-advisory/qsa-22-16

Affected products (15)

cpe:2.3:a:qnap:qts:*:*:*:*:*:*:*:*
cpe:2.3:o:qnap:qts:*:*:*:*:*:*:*:*
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:*:*:*:*:*:*
cpe:2.3:o:qnap:qts:4.2.6:build_20210327:*:*:*:*:*:*
cpe:2.3:o:qnap:qts:4.2.6:build_20211215:*:*:*:*:*:*
cpe:2.3:o:qnap:quts_hero:*:*:*:*:*:*:*:*
cpe:2.3:o:qnap:qutscloud:*:*:*:*:*:*:*:*

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