How severe is CVE-2021-34827?

CVE-2021-34827 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-34827 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-34827?

CVE-2021-34827 affects Dlink Dap-1330 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-34827?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-34827 published?

CVE-2021-34827 was published on 2021-07-15 and last updated on 2026-06-17.

CVE-2021-34827

CVE-2021-34827 is a high-severity vulnerability in Dlink Dap-1330 Firmware with a CVSS 3.x base score of 8.8. 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-121.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 8.3
EPSS exploit prediction: 2% (82nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-121
Affected product: Dlink Dap-1330 Firmware
Published: 2021-07-15
Last modified: 2026-06-17

Description

This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of D-Link DAP-1330 1.13B01 BETA routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the handling of the SOAPAction HTTP header. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of the device. Was ZDI-CAN-12029.

Frequently asked questions

What is CVE-2021-34827?: This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of D-Link DAP-1330 1.13B01 BETA routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the handling of the SOAPAction HTTP header. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of the device. Was ZDI-CAN-12029.
How severe is CVE-2021-34827?: CVE-2021-34827 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-34827 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-34827?: CVE-2021-34827 affects Dlink Dap-1330 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-34827?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-34827 published?: CVE-2021-34827 was published on 2021-07-15 and last updated on 2026-06-17.

References

https://www.zerodayinitiative.com/advisories/ZDI-21-679/

Affected products (1)

cpe:2.3:o:dlink:dap-1330_firmware:1.13b01:beta:*:*:*:*:*:*

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