How severe is CVE-2021-21726?

CVE-2021-21726 has a CVSS 3.x base score of 2.3, rated low severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2021-21726 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-21726?

CVE-2021-21726 primarily affects Zte Zxone 9700 Firmware. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-21726?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-21726 published?

CVE-2021-21726 was published on 2021-03-12 and last updated on 2026-06-17.

CVE-2021-21726

CVE-2021-21726 is a low-severity vulnerability in Zte Zxone 9700 Firmware with a CVSS 3.x base score of 2.3. 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-20.

Key facts

Severity: Low (CVSS 3.x base score 2.3)
CVSS v2: 2.1
EPSS exploit prediction: 0% (31st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Zte Zxone 9700 Firmware
Published: 2021-03-12
Last modified: 2026-06-17

Description

Some ZTE products have an input verification vulnerability in the diagnostic function interface. Due to insufficient verification of some parameters input by users, an attacker with high privileges can cause process exception by repeatedly inputting illegal parameters. This affects:<ZXONE 9700 , ZXONE 8700, ZXONE 19700><V1.40.021.021CP049, V1.0P02B219_@NCPM-RELEASE_2.40R1-20200914.set>

Frequently asked questions

What is CVE-2021-21726?: Some ZTE products have an input verification vulnerability in the diagnostic function interface. Due to insufficient verification of some parameters input by users, an attacker with high privileges can cause process exception by repeatedly inputting illegal parameters. This affects:<ZXONE 9700 , ZXONE 8700, ZXONE 19700><V1.40.021.021CP049, V1.0P02B219_@NCPM-RELEASE_2.40R1-20200914.set>
How severe is CVE-2021-21726?: CVE-2021-21726 has a CVSS 3.x base score of 2.3, rated low severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2021-21726 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-21726?: CVE-2021-21726 primarily affects Zte Zxone 9700 Firmware. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-21726?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-21726 published?: CVE-2021-21726 was published on 2021-03-12 and last updated on 2026-06-17.

References

http://support.zte.com.cn/support/news/LoopholeInfoDetail.aspx?newsId=1014664

Affected products (3)

cpe:2.3:o:zte:zxone_9700_firmware:1.40.021.021cp049:*:*:*:*:*:*:*
cpe:2.3:o:zte:zxone_8700_firmware:1.40.021.021cp049:*:*:*:*:*:*:*
cpe:2.3:o:zte:zxone_19700_firmware:1.0p02b219_\@ncpm-release_2.40r1-20200914.set:*:*:*:*:*:*:*

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