How severe is CVE-2021-26620?

CVE-2021-26620 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-26620 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-26620?

CVE-2021-26620 primarily affects Iptime Nas101 Firmware. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-26620?

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-2021-26620 published?

CVE-2021-26620 was published on 2022-03-25 and last updated on 2026-06-17.

CVE-2021-26620

CVE-2021-26620 is a high-severity vulnerability in Iptime Nas101 Firmware with a CVSS 3.x base score of 7.5. 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-287.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (67th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Iptime Nas101 Firmware
Published: 2022-03-25
Last modified: 2026-06-17

Description

An improper authentication vulnerability leading to information leakage was discovered in iptime NAS2dual. Remote attackers are able to steal important information in the server by exploiting vulnerabilities such as insufficient authentication when accessing the shared folder and changing user’s passwords.

Frequently asked questions

What is CVE-2021-26620?: An improper authentication vulnerability leading to information leakage was discovered in iptime NAS2dual. Remote attackers are able to steal important information in the server by exploiting vulnerabilities such as insufficient authentication when accessing the shared folder and changing user’s passwords.
How severe is CVE-2021-26620?: CVE-2021-26620 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-26620 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-26620?: CVE-2021-26620 primarily affects Iptime Nas101 Firmware. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-26620?: 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-2021-26620 published?: CVE-2021-26620 was published on 2022-03-25 and last updated on 2026-06-17.

References

https://www.krcert.or.kr/krcert/secNoticeView.do?bulletin_writing_sequence=66578

Affected products (9)

cpe:2.3:o:iptime:nas101_firmware:*:*:*:*:*:windows:*:*
cpe:2.3:o:iptime:nas1dual_firmware:*:*:*:*:*:windows:*:*
cpe:2.3:o:iptime:nas2dual_firmware:*:*:*:*:*:windows:*:*
cpe:2.3:o:iptime:nas3_firmware:*:*:*:*:*:windows:*:*
cpe:2.3:o:iptime:nas4_firmware:*:*:*:*:*:windows:*:*
cpe:2.3:o:iptime:nas4dual_firmware:*:*:*:*:*:windows:*:*
cpe:2.3:o:iptime:nas-i_firmware:*:*:*:*:*:windows:*:*
cpe:2.3:o:iptime:nas-ii_firmware:*:*:*:*:*:windows:*:*
cpe:2.3:o:iptime:nas-iie_firmware:*:*:*:*:*:windows:*:*

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