CVE-2020-6871

CVE-2020-6871 is a critical-severity vulnerability in Zte R8500g4 Firmware with a CVSS 3.x base score of 9.8. 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: Critical (CVSS 3.x base score 9.8)
• CVSS v2: 7.5
• EPSS exploit prediction: 2% (77th percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-287
• Affected product: Zte R8500g4 Firmware
• Published: 2020-07-20
• Last modified: 2026-06-17

Description

The server management software module of ZTE has an authentication issue vulnerability, which allows users to skip the authentication of the server and execute some commands for high-level users. This affects: <R5300G4V03.08.0100/V03.07.0300/V03.07.0200/V03.07.0108/V03.07.0100/V03.05.0047/V03.05.0046/V03.05.0045/V03.05.0044/V03.05.0043/V03.05.0040/V03.04.0020;R8500G4V03.07.0103/V03.07.0101/V03.06.0100/V03.05.0400/V03.05.0020;R5500G4V03.08.0100/V03.07.0200/V03.07.0100/V03.06.0100>

Frequently asked questions

What is CVE-2020-6871?

The server management software module of ZTE has an authentication issue vulnerability, which allows users to skip the authentication of the server and execute some commands for high-level users. This affects: <R5300G4V03.08.0100/V03.07.0300/V03.07.0200/V03.07.0108/V03.07.0100/V03.05.0047/V03.05.0046/V03.05.0045/V03.05.0044/V03.05.0043/V03.05.0040/V03.04.0020;R8500G4V03.07.0103/V03.07.0101/V03.06.0100/V03.05.0400/V03.05.0020;R5500G4V03.08.0100/V03.07.0200/V03.07.0100/V03.06.0100>

How severe is CVE-2020-6871?

CVE-2020-6871 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-6871 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-6871?

CVE-2020-6871 primarily affects Zte R8500g4 Firmware. In total, 21 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-6871?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2020-6871 published?

CVE-2020-6871 was published on 2020-07-20 and last updated on 2026-06-17.

References

• http://support.zte.com.cn/support/news/LoopholeInfoDetail.aspx?newsId=1013203

Affected products (21)

• cpe:2.3:o:zte:r8500g4_firmware:03.05.0020:*:*:*:*:*:*:*
• cpe:2.3:o:zte:r8500g4_firmware:03.05.0400:*:*:*:*:*:*:*
• cpe:2.3:o:zte:r8500g4_firmware:03.06.0100:*:*:*:*:*:*:*
• cpe:2.3:o:zte:r8500g4_firmware:03.07.0101:*:*:*:*:*:*:*
• cpe:2.3:o:zte:r8500g4_firmware:03.07.0103:*:*:*:*:*:*:*
• cpe:2.3:o:zte:r5500g4_firmware:03.06.0100:*:*:*:*:*:*:*
• cpe:2.3:o:zte:r5500g4_firmware:03.07.0100:*:*:*:*:*:*:*
• cpe:2.3:o:zte:r5500g4_firmware:03.07.0200:*:*:*:*:*:*:*
• cpe:2.3:o:zte:r5500g4_firmware:03.08.0100:*:*:*:*:*:*:*
• cpe:2.3:o:zte:r5300g4_firmware:03.04.0020:*:*:*:*:*:*:*
• cpe:2.3:o:zte:r5300g4_firmware:03.05.0040:*:*:*:*:*:*:*
• cpe:2.3:o:zte:r5300g4_firmware:03.05.0043:*:*:*:*:*:*:*
• cpe:2.3:o:zte:r5300g4_firmware:03.05.0044:*:*:*:*:*:*:*
• cpe:2.3:o:zte:r5300g4_firmware:03.05.0045:*:*:*:*:*:*:*
• cpe:2.3:o:zte:r5300g4_firmware:03.05.0046:*:*:*:*:*:*:*
• cpe:2.3:o:zte:r5300g4_firmware:03.05.0047:*:*:*:*:*:*:*
• cpe:2.3:o:zte:r5300g4_firmware:03.07.0100:*:*:*:*:*:*:*
• cpe:2.3:o:zte:r5300g4_firmware:03.07.0108:*:*:*:*:*:*:*
• cpe:2.3:o:zte:r5300g4_firmware:03.07.0200:*:*:*:*:*:*:*
• cpe:2.3:o:zte:r5300g4_firmware:03.07.0300:*:*:*:*:*:*:*
• cpe:2.3:o:zte:r5300g4_firmware:03.08.0100:*:*:*:*:*:*:*

More vulnerabilities in Zte R8500g4 Firmware

• CVE-2020-6872 — Medium (CVSS 6.1): The server management software module of ZTE has a storage XSS vulnerability. The attacker inserts some attack codes…

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Other CWE-287 (Improper Authentication) vulnerabilities

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• CVE-2026-10611 — Critical (CVSS 10.0): An authentication bypass vulnerability exists in MISP when LDAP mixed authentication is enabled with OTP enforcement.…
• CVE-2026-47280 — Critical (CVSS 10.0): Improper authentication in Azure Resource Manager (ARM) allows an unauthorized attacker to elevate privileges over a…
• CVE-2026-42822 — Critical (CVSS 10.0): Improper authentication in Azure Local Disconnected Operations allows an unauthorized attacker to elevate privileges…
• CVE-2026-20182 — Critical (CVSS 10.0): May 2026: This security advisory provides the details and fix information for a vulnerability that was discovered and…

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