How severe is CVE-2021-33265?

CVE-2021-33265 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-2021-33265 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 14% (96th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-33265?

CVE-2021-33265 affects Dlink Dir-809 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-33265?

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-2021-33265 published?

CVE-2021-33265 was published on 2021-12-01 and last updated on 2026-06-17.

CVE-2021-33265

CVE-2021-33265 is a critical-severity vulnerability in Dlink Dir-809 Firmware with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 14% places it in the 96th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-787.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.2
EPSS exploit prediction: 14% (96th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Dlink Dir-809 Firmware
Published: 2021-12-01
Last modified: 2026-06-17

Description

D-Link DIR-809 devices with firmware through DIR-809Ax_FW1.12WWB03_20190410 were discovered to contain a stack buffer overflow vulnerability in the function FUN_80046eb4 in /formSetPortTr. This vulnerability is triggered via a crafted POST request.

Frequently asked questions

What is CVE-2021-33265?: D-Link DIR-809 devices with firmware through DIR-809Ax_FW1.12WWB03_20190410 were discovered to contain a stack buffer overflow vulnerability in the function FUN_80046eb4 in /formSetPortTr. This vulnerability is triggered via a crafted POST request.
How severe is CVE-2021-33265?: CVE-2021-33265 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-2021-33265 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 14% (96th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-33265?: CVE-2021-33265 affects Dlink Dir-809 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-33265?: 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-2021-33265 published?: CVE-2021-33265 was published on 2021-12-01 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:dlink:dir-809_firmware:*:*:*:*:*:*:*:*

More vulnerabilities in Dlink Dir-809 Firmware

CVE-2021-33274 — Critical (CVSS 9.8): D-Link DIR-809 devices with firmware through DIR-809Ax_FW1.12WWB03_20190410 were discovered to contain a stack buffer…
CVE-2021-33271 — Critical (CVSS 9.8): D-Link DIR-809 devices with firmware through DIR-809Ax_FW1.12WWB03_20190410 were discovered to contain a stack buffer…
CVE-2021-33270 — Critical (CVSS 9.8): D-Link DIR-809 devices with firmware through DIR-809Ax_FW1.12WWB03_20190410 were discovered to contain a stack buffer…
CVE-2021-33269 — Critical (CVSS 9.8): D-Link DIR-809 devices with firmware through DIR-809Ax_FW1.12WWB03_20190410 were discovered to contain a stack buffer…
CVE-2021-33268 — Critical (CVSS 9.8): D-Link DIR-809 devices with firmware through DIR-809Ax_FW1.12WWB03_20190410 were discovered to contain a stack buffer…
CVE-2021-33267 — Critical (CVSS 9.8): D-Link DIR-809 devices with firmware through DIR-809Ax_FW1.12WWB03_20190410 were discovered to contain a stack buffer…

All CVEs affecting Dlink Dir-809 Firmware →

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