How severe is CVE-2021-26621?

CVE-2021-26621 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-26621 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-26621?

CVE-2021-26621 affects Netu Mex01 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-26621?

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-2021-26621 published?

CVE-2021-26621 was published on 2022-03-25 and last updated on 2026-06-17.

CVE-2021-26621

CVE-2021-26621 is a high-severity vulnerability in Netu Mex01 Firmware with a CVSS 3.x base score of 8.1. 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-120.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v2: 7.5
EPSS exploit prediction: 2% (73rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-120
Affected product: Netu Mex01 Firmware
Published: 2022-03-25
Last modified: 2026-06-17

Description

An Buffer Overflow vulnerability leading to remote code execution was discovered in MEX01. Remote attackers can use this vulnerability by using the property that the target program copies parameter values to memory through the strcpy() function.

Frequently asked questions

What is CVE-2021-26621?: An Buffer Overflow vulnerability leading to remote code execution was discovered in MEX01. Remote attackers can use this vulnerability by using the property that the target program copies parameter values to memory through the strcpy() function.
How severe is CVE-2021-26621?: CVE-2021-26621 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-26621 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-26621?: CVE-2021-26621 affects Netu Mex01 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-26621?: 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-2021-26621 published?: CVE-2021-26621 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=66579

Affected products (1)

cpe:2.3:o:netu:mex01_firmware:*:*:*:*:*:*:*:*

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