How severe is CVE-2020-24987?

CVE-2020-24987 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-2020-24987 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-24987?

CVE-2020-24987 affects Tendacn Ac18 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-24987?

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-2020-24987 published?

CVE-2020-24987 was published on 2020-09-04 and last updated on 2026-06-17.

CVE-2020-24987

CVE-2020-24987 is a critical-severity vulnerability in Tendacn Ac18 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: 6.8
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Tendacn Ac18 Firmware
Published: 2020-09-04
Last modified: 2026-06-17

Description

Tenda AC18 Router through V15.03.05.05_EN and through V15.03.05.19(6318) CN devices could cause a remote code execution due to incorrect authentication handling of vulnerable logincheck() function in /usr/lib/lua/ngx_authserver/ngx_wdas.lua file if the administrator UI Interface is set to "radius".

Frequently asked questions

What is CVE-2020-24987?: Tenda AC18 Router through V15.03.05.05_EN and through V15.03.05.19(6318) CN devices could cause a remote code execution due to incorrect authentication handling of vulnerable logincheck() function in /usr/lib/lua/ngx_authserver/ngx_wdas.lua file if the administrator UI Interface is set to "radius".
How severe is CVE-2020-24987?: CVE-2020-24987 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-2020-24987 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-24987?: CVE-2020-24987 affects Tendacn Ac18 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-24987?: 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-2020-24987 published?: CVE-2020-24987 was published on 2020-09-04 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:tendacn:ac18_firmware:*:*:*:*:*:*:*:*

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Other CWE-287 (Improper Authentication) vulnerabilities

CVE-2026-45480 — Critical (CVSS 10.0): Improper authentication in Azure Active Directory allows an unauthorized attacker to elevate privileges over a network.
CVE-2026-46389 — Critical (CVSS 10.0): UDS Identity Config builds the Keycloak configuration image (realm, plugins, theme, truststore, JARs) consumed by UDS…
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…

Browse all CWE-287 (Improper Authentication) vulnerabilities →