CVE-2021-44053

mediumpriority · track · 24EPSS 0.008 · 55 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.76% (55th) EPSS

CVSS 4.3 · medium

Is it mine?

32 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · fstec_bdu

EPSS · scored 2026-10-27

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

cvss

Technical severity, 0–10. One row per scoring source.

6.1

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 8.6 · impact 2.9

v3.16.1mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 2.7

v3.16.1mediumAV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:Nsecondary · FSTEC (BDU) RU

v3.15.7mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:Nsecondary · ENISA EU

v3.15.7mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:Nsecondary · security@qnapsecurity.com.twexploitability 2.1 · impact 3.6

v3.15.6mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-79USprimaryCWE-79US

affected products (32)

Products and version ranges known to be affected.

QNAP Systems Inc. QTSunspecified → 4.5.4.1991 build 20220329enisa_euvdEU
QNAP Systems Inc. QTSunspecified → 5.0.0.1986 build 20220324enisa_euvdEU
QNAP Systems Inc. QuTS herounspecified → h4.5.4.1971 build 20220310enisa_euvdEU
QNAP Systems Inc. QuTS herounspecified → h5.0.0.1986 build 20220324enisa_euvdEU
QNAP Systems Inc. QuTScloudunspecified → c5.0.1.1949enisa_euvdEU
QNAP Systems, Inc. QTS≤ 4.2.6build 20190322fstec_bduRU
QNAP Systems, Inc. QTS≤ 4.2.6build 20170517fstec_bduRU
QNAP Systems, Inc. QTS≤ 4.2.6build 20211215fstec_bduRU
QNAP Systems, Inc. QTS≤ 4.2.6build 20200109fstec_bduRU
QNAP Systems, Inc. QTS≤ 4.2.6build 20191107fstec_bduRU
QNAP Systems, Inc. QTS≤ 4.2.6build 20190921fstec_bduRU
QNAP Systems, Inc. QTS≤ 4.2.6build 20190730fstec_bduRU
QNAP Systems, Inc. QTS≤ 4.2.6build 20200821fstec_bduRU
QNAP Systems, Inc. QTS≤ 4.2.6build 20200611fstec_bduRU
QNAP Systems, Inc. QTS≤ 4.2.6build 20200421fstec_bduRU
QNAP Systems, Inc. QTS4.3.3.0174 → 4.3.3.1945fstec_bduRU
QNAP Systems, Inc. QTS4.3.4.0899 → 4.3.4.1976fstec_bduRU
QNAP Systems, Inc. QTS4.3.6.0895 → 4.3.6.1965fstec_bduRU
QNAP Systems, Inc. QTS4.4.0.0883 → 4.5.4.1991fstec_bduRU
QNAP Systems, Inc. QTS5.0.0.1716 → 5.0.0.1986fstec_bduRU

showing 20 of 32

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu NVD CVE.org MITRE

published 2022-05-05modified 2026-06-17

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+53007 more

references (5)

External citations — patches, advisories, analysis.

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