How severe is CVE-2020-6881?

CVE-2020-6881 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 none, integrity none, and availability high.

Is CVE-2020-6881 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-6881?

CVE-2020-6881 primarily affects Zte Zxhn E8810 Firmware. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-6881?

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-2020-6881 published?

CVE-2020-6881 was published on 2020-12-21 and last updated on 2026-06-17.

CVE-2020-6881

CVE-2020-6881 is a high-severity vulnerability in Zte Zxhn E8810 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-346.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (44th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-346
Affected product: Zte Zxhn E8810 Firmware
Published: 2020-12-21
Last modified: 2026-06-17

Description

ZTE E8810/E8820/E8822 series routers have an MQTT DoS vulnerability, which is caused by the failure of the device to verify the validity of abnormal messages. A remote attacker could connect to the MQTT server and send an MQTT exception message to the specified device, which will cause the device to deny service. This affects:<ZXHN E8810, ZXHN E8820, ZXHN E8822><E8810 V1.0.26, E8810 V2.0.1, E8820 V1.1.3L, E8820 V2.0.13, E8822 V2.0.13>

Frequently asked questions

What is CVE-2020-6881?: ZTE E8810/E8820/E8822 series routers have an MQTT DoS vulnerability, which is caused by the failure of the device to verify the validity of abnormal messages. A remote attacker could connect to the MQTT server and send an MQTT exception message to the specified device, which will cause the device to deny service. This affects:<ZXHN E8810, ZXHN E8820, ZXHN E8822><E8810 V1.0.26, E8810 V2.0.1, E8820 V1.1.3L, E8820 V2.0.13, E8822 V2.0.13>
How severe is CVE-2020-6881?: CVE-2020-6881 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 none, integrity none, and availability high.
Is CVE-2020-6881 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-6881?: CVE-2020-6881 primarily affects Zte Zxhn E8810 Firmware. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-6881?: 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-2020-6881 published?: CVE-2020-6881 was published on 2020-12-21 and last updated on 2026-06-17.

References

http://support.zte.com.cn/support/news/LoopholeInfoDetail.aspx?newsId=1014202

Affected products (5)

cpe:2.3:o:zte:zxhn_e8810_firmware:1.0.26:*:*:*:*:*:*:*
cpe:2.3:o:zte:zxhn_e8810_firmware:2.0.1:*:*:*:*:*:*:*
cpe:2.3:o:zte:zxhn_e8820_firmware:1.1.3:*:*:*:*:*:*:*
cpe:2.3:o:zte:zxhn_e8820_firmware:2.0.13:*:*:*:*:*:*:*
cpe:2.3:o:zte:zxhn_e8822_firmware:2.0.13:*:*:*:*:*:*:*

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