How severe is CVE-2021-21724?

CVE-2021-21724 has a CVSS 3.x base score of 4.4, rated medium 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 high.

Is CVE-2021-21724 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-21724?

CVE-2021-21724 affects Zte Zxr10 8900e Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-21724?

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

When was CVE-2021-21724 published?

CVE-2021-21724 was published on 2021-02-26 and last updated on 2026-06-17.

CVE-2021-21724

CVE-2021-21724 is a medium-severity vulnerability in Zte Zxr10 8900e Firmware with a CVSS 3.x base score of 4.4. 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-401.

Key facts

Severity: Medium (CVSS 3.x base score 4.4)
CVSS v2: 2.1
EPSS exploit prediction: 0% (28th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-401
Affected product: Zte Zxr10 8900e Firmware
Published: 2021-02-26
Last modified: 2026-06-17

Description

A ZTE product has a memory leak vulnerability. Due to the product's improper handling of memory release in certain scenarios, a local attacker with device permissions repeatedly attenuated the optical signal to cause memory leak and abnormal service. This affects: ZXR10 8900E, all versions up to V3.03.20R2B30P1.

Frequently asked questions

What is CVE-2021-21724?: A ZTE product has a memory leak vulnerability. Due to the product's improper handling of memory release in certain scenarios, a local attacker with device permissions repeatedly attenuated the optical signal to cause memory leak and abnormal service. This affects: ZXR10 8900E, all versions up to V3.03.20R2B30P1.
How severe is CVE-2021-21724?: CVE-2021-21724 has a CVSS 3.x base score of 4.4, rated medium 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 high.
Is CVE-2021-21724 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-21724?: CVE-2021-21724 affects Zte Zxr10 8900e Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-21724?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-21724 published?: CVE-2021-21724 was published on 2021-02-26 and last updated on 2026-06-17.

References

http://support.zte.com.cn/support/news/LoopholeInfoDetail.aspx?newsId=1014584

Affected products (1)

cpe:2.3:o:zte:zxr10_8900e_firmware:*:*:*:*:*:*:*:*

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