CVE-2021-44052

mediumpriority · track · 33EPSS 0.016 · 76 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.59% (76th) EPSS

CVSS 5.5 · medium

Is it mine?

36 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · fstec_bdu

EPSS · scored 2026-10-27

An improper link resolution before file access ('Link Following') vulnerability has been reported to affect QNAP device running QuTScloud, QuTS hero, and QTS. If exploited, this vulnerability allows remote attackers to traverse the file system to unintended locations and read or overwrite the contents of unexpected files. We have already fixed this vulnerability in the following versions of QuTScloud, QuTS hero, and QTS: QuTScloud c5.0.1.1998 and later QuTS hero h4.5.4.1971 build 20220310 and later QuTS hero h5.0.0.1986 build 20220324 and later QTS 4.3.4.1976 build 20220303 and later QTS 4.3.3.1945 build 20220303 and later QTS 4.2.6 build 20220304 and later QTS 4.3.6.1965 build 20220302 and later QTS 5.0.0.1986 build 20220324 and later QTS 4.5.4.1991 build 20220329 and later

cvss

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

8.1

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.5–8.1

v2.05.5mediumAV:N/AC:L/Au:S/C:P/I:P/A:Nprimary · NVD / NIST USexploitability 8 · impact 4.9

v3.18.1highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 5.2

v3.18.1highAV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Nsecondary · FSTEC (BDU) RU

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:Nsecondary · ENISA EU

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:Nsecondary · security@qnapsecurity.com.twexploitability 2.8 · impact 3.6

v3.17.4highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-59USprimaryCWE-59US

affected products (36)

Products and version ranges known to be affected.

QNAP Systems Inc. QTSunspecified → 4.2.6 build 20220304enisa_euvdEU
QNAP Systems Inc. QTSunspecified → 4.3.3.1945 build 20220303enisa_euvdEU
QNAP Systems Inc. QTSunspecified → 4.3.4.1976 build 20220303enisa_euvdEU
QNAP Systems Inc. QTSunspecified → 4.3.6.1965 build 20220302enisa_euvdEU
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 → c5.0.1.1998enisa_euvdEU
QNAP Systems, Inc. QTS≤ 4.2.6build 20200109fstec_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 20210327fstec_bduRU
QNAP Systems, Inc. QTS≤ 4.2.6build 20191107fstec_bduRU
QNAP Systems, Inc. QTS≤ 4.2.6build 20190322fstec_bduRU
QNAP Systems, Inc. QTS≤ 4.2.6build 20190730fstec_bduRU
QNAP Systems, Inc. QTS≤ 4.2.6build 20190921fstec_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

showing 20 of 36

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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references (5)

External citations — patches, advisories, analysis.

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