How severe is CVE-2021-20158?

CVE-2021-20158 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-2021-20158 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 11% (95th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20158?

CVE-2021-20158 affects Trendnet Tew-827dru Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-20158?

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-2021-20158 published?

CVE-2021-20158 was published on 2021-12-30 and last updated on 2026-06-17.

CVE-2021-20158

CVE-2021-20158 is a critical-severity vulnerability in Trendnet Tew-827dru Firmware with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 11% places it in the 95th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-306.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 11% (95th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-306
Affected product: Trendnet Tew-827dru Firmware
Published: 2021-12-30
Last modified: 2026-06-17

Description

Trendnet AC2600 TEW-827DRU version 2.08B01 contains an authentication bypass vulnerability. It is possible for an unauthenticated, malicous actor to force the change of the admin password due to a hidden administrative command.

Frequently asked questions

What is CVE-2021-20158?: Trendnet AC2600 TEW-827DRU version 2.08B01 contains an authentication bypass vulnerability. It is possible for an unauthenticated, malicous actor to force the change of the admin password due to a hidden administrative command.
How severe is CVE-2021-20158?: CVE-2021-20158 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-2021-20158 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 11% (95th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20158?: CVE-2021-20158 affects Trendnet Tew-827dru Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-20158?: 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-2021-20158 published?: CVE-2021-20158 was published on 2021-12-30 and last updated on 2026-06-17.

References

https://www.tenable.com/security/research/tra-2021-54

Affected products (1)

cpe:2.3:o:trendnet:tew-827dru_firmware:2.08b01:*:*:*:*:*:*:*

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