CVE-2021-44052
CVE-2021-44052 is a medium-severity vulnerability in Qnap Qts with a CVSS 3.x base score of 6.5. 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-59.
Key facts
- Severity: Medium (CVSS 3.x base score 6.5)
- CVSS v2: 5.5
- EPSS exploit prediction: 1% (71st percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-59
- Affected product: Qnap Qts
- Published:
- Last modified:
Description
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
Frequently asked questions
- What is CVE-2021-44052?
- 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
- How severe is CVE-2021-44052?
- CVE-2021-44052 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
- Is CVE-2021-44052 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-44052?
- CVE-2021-44052 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-2021-44052?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-44052 published?
- CVE-2021-44052 was published on 2022-05-05 and last updated on 2026-06-17.
References
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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