How severe is CVE-2020-29557?

CVE-2020-29557 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-2020-29557 being actively exploited?

Yes. CVE-2020-29557 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2021-11-03, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2020-29557?

CVE-2020-29557 affects Dlink Dir-825 R1 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-29557?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2020-29557 have an EU (EUVD) identifier?

Yes. CVE-2020-29557 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2020-21920. It is also flagged as exploited in the EUVD (since 2021-11-03).

When was CVE-2020-29557 published?

CVE-2020-29557 was published on 2021-01-29 and last updated on 2026-06-17.

CVE-2020-29557

CVE-2020-29557 is a critical-severity vulnerability in Dlink Dir-825 R1 Firmware with a CVSS 3.x base score of 9.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2021-11-03). The underlying weakness is classified as CWE-119.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
EPSS exploit prediction: 54% (99th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2021-11-03)
EU (EUVD) id: EUVD-2020-21920
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2021-11-03)
Weakness: CWE-119
Affected product: Dlink Dir-825 R1 Firmware
Published: 2021-01-29
Last modified: 2026-06-17

Description

An issue was discovered on D-Link DIR-825 R1 devices through 3.0.1 before 2020-11-20. A buffer overflow in the web interface allows attackers to achieve pre-authentication remote code execution.

Frequently asked questions

What is CVE-2020-29557?: An issue was discovered on D-Link DIR-825 R1 devices through 3.0.1 before 2020-11-20. A buffer overflow in the web interface allows attackers to achieve pre-authentication remote code execution.
How severe is CVE-2020-29557?: CVE-2020-29557 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-2020-29557 being actively exploited?: Yes. CVE-2020-29557 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2021-11-03, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2020-29557?: CVE-2020-29557 affects Dlink Dir-825 R1 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-29557?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2020-29557 have an EU (EUVD) identifier?: Yes. CVE-2020-29557 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2020-21920. It is also flagged as exploited in the EUVD (since 2021-11-03).
When was CVE-2020-29557 published?: CVE-2020-29557 was published on 2021-01-29 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:dlink:dir-825_r1_firmware:*:*:*:*:*:*:*:*

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