How severe is CVE-2021-44051?

CVE-2021-44051 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-44051 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-44051?

CVE-2021-44051 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-2021-44051?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-44051 published?

CVE-2021-44051 was published on 2022-05-05 and last updated on 2026-06-17.

CVE-2021-44051

CVE-2021-44051 is a high-severity vulnerability in Qnap Qts with a CVSS 3.x base score of 8.8. 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-77.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 2% (73rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-77
Affected product: Qnap Qts
Published: 2022-05-05
Last modified: 2026-06-17

Description

A command injection vulnerability has been reported to affect QNAP NAS running QuTScloud, QuTS hero and QTS. If exploited, this vulnerability allows remote attackers to run arbitrary commands. We have already fixed this vulnerability in the following versions of QuTScloud, QuTS hero and QTS: QuTScloud c5.0.1.1949 and later QuTS hero h5.0.0.1986 build 20220324 and later QTS 5.0.0.1986 build 20220324 and later

Frequently asked questions

What is CVE-2021-44051?: A command injection vulnerability has been reported to affect QNAP NAS running QuTScloud, QuTS hero and QTS. If exploited, this vulnerability allows remote attackers to run arbitrary commands. We have already fixed this vulnerability in the following versions of QuTScloud, QuTS hero and QTS: QuTScloud c5.0.1.1949 and later QuTS hero h5.0.0.1986 build 20220324 and later QTS 5.0.0.1986 build 20220324 and later
How severe is CVE-2021-44051?: CVE-2021-44051 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-44051 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-44051?: CVE-2021-44051 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-2021-44051?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-44051 published?: CVE-2021-44051 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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