How severe is CVE-2021-20697?

CVE-2021-20697 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-2021-20697 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20697?

CVE-2021-20697 affects Dlink Dap-1880ac Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-20697?

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-2021-20697 published?

CVE-2021-20697 was published on 2021-04-26 and last updated on 2026-06-17.

CVE-2021-20697

CVE-2021-20697 is a critical-severity vulnerability in Dlink Dap-1880ac 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-306.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 2% (75th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-306
Affected product: Dlink Dap-1880ac Firmware
Published: 2021-04-26
Last modified: 2026-06-17

Description

Missing authentication for critical function in DAP-1880AC firmware version 1.21 and earlier allows a remote attacker to login to the device as an authenticated user without the access privilege via unspecified vectors.

Frequently asked questions

What is CVE-2021-20697?: Missing authentication for critical function in DAP-1880AC firmware version 1.21 and earlier allows a remote attacker to login to the device as an authenticated user without the access privilege via unspecified vectors.
How severe is CVE-2021-20697?: CVE-2021-20697 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-2021-20697 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20697?: CVE-2021-20697 affects Dlink Dap-1880ac Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-20697?: 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-2021-20697 published?: CVE-2021-20697 was published on 2021-04-26 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:dlink:dap-1880ac_firmware:*:*:*:*:*:*:*:*

More vulnerabilities in Dlink Dap-1880ac Firmware

CVE-2021-20696 — High (CVSS 8.8): DAP-1880AC firmware version 1.21 and earlier allows a remote authenticated attacker to execute arbitrary OS commands by…
CVE-2021-20695 — High (CVSS 8.8): Improper following of a certificate's chain of trust vulnerability in DAP-1880AC firmware version 1.21 and earlier…
CVE-2021-20694 — High (CVSS 8.8): Improper access control vulnerability in DAP-1880AC firmware version 1.21 and earlier allows a remote authenticated…

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