How severe is CVE-2018-0721?

CVE-2018-0721 has a CVSS 3.x base score of 7.7, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity high, and availability low.

Is CVE-2018-0721 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-0721?

CVE-2018-0721 primarily affects Qnap Qts. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-0721?

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-2018-0721 published?

CVE-2018-0721 was published on 2018-11-27 and last updated on 2026-06-17.

CVE-2018-0721

CVE-2018-0721 is a high-severity vulnerability in Qnap Qts with a CVSS 3.x base score of 7.7. 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-119.

Key facts

Severity: High (CVSS 3.x base score 7.7)
CVSS v2: 10.0
EPSS exploit prediction: 2% (72nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-119
Affected product: Qnap Qts
Published: 2018-11-27
Last modified: 2026-06-17

Description

Buffer Overflow vulnerability in NAS devices. QTS allows attackers to run arbitrary code. This issue affects: QNAP Systems Inc. QTS version 4.2.6 and prior versions on build 20180711; version 4.3.3 and prior versions on build 20180725; version 4.3.4 and prior versions on build 20180710.

Frequently asked questions

What is CVE-2018-0721?: Buffer Overflow vulnerability in NAS devices. QTS allows attackers to run arbitrary code. This issue affects: QNAP Systems Inc. QTS version 4.2.6 and prior versions on build 20180711; version 4.3.3 and prior versions on build 20180725; version 4.3.4 and prior versions on build 20180710.
How severe is CVE-2018-0721?: CVE-2018-0721 has a CVSS 3.x base score of 7.7, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity high, and availability low.
Is CVE-2018-0721 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-0721?: CVE-2018-0721 primarily affects Qnap Qts. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-0721?: 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-2018-0721 published?: CVE-2018-0721 was published on 2018-11-27 and last updated on 2026-06-17.

References

https://www.qnap.com/zh-tw/security-advisory/nas-201809-20

Affected products (3)

cpe:2.3:o:qnap:qts:4.2.6:*:*:*:*:*:*:*
cpe:2.3:o:qnap:qts:4.3.3:*:*:*:*:*:*:*
cpe:2.3:o:qnap:qts:4.3.4:*:*:*:*:*:*:*

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