How severe is CVE-2026-4181?

CVE-2026-4181 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-2026-4181 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-4181?

CVE-2026-4181 affects Dlink Dir-816 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-4181?

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.

Does CVE-2026-4181 have an EU (EUVD) identifier?

Yes. CVE-2026-4181 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-12233.

When was CVE-2026-4181 published?

CVE-2026-4181 was published on 2026-03-16 and last updated on 2026-06-17.

CVE-2026-4181

CVE-2026-4181 is a critical-severity vulnerability in Dlink Dir-816 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-787.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
CVSS v4: 8.9
EPSS exploit prediction: 1% (64th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-12233
Weakness: CWE-787
Affected product: Dlink Dir-816 Firmware
Published: 2026-03-16
Last modified: 2026-06-17

Description

A security flaw has been discovered in D-Link DIR-816 1.10CNB05. This affects an unknown function of the file /goform/form2RepeaterStep2.cgi of the component goahead. The manipulation of the argument key1/key2/key3/key4/pskValue results in stack-based buffer overflow. The attack may be launched remotely. The exploit has been released to the public and may be used for attacks. This vulnerability only affects products that are no longer supported by the maintainer.

Frequently asked questions

What is CVE-2026-4181?: A security flaw has been discovered in D-Link DIR-816 1.10CNB05. This affects an unknown function of the file /goform/form2RepeaterStep2.cgi of the component goahead. The manipulation of the argument key1/key2/key3/key4/pskValue results in stack-based buffer overflow. The attack may be launched remotely. The exploit has been released to the public and may be used for attacks. This vulnerability only affects products that are no longer supported by the maintainer.
How severe is CVE-2026-4181?: CVE-2026-4181 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-2026-4181 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-4181?: CVE-2026-4181 affects Dlink Dir-816 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-4181?: 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.
Does CVE-2026-4181 have an EU (EUVD) identifier?: Yes. CVE-2026-4181 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-12233.
When was CVE-2026-4181 published?: CVE-2026-4181 was published on 2026-03-16 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:dlink:dir-816_firmware:1.10cnb05:*:*:*:*:*:*:*

More vulnerabilities in Dlink Dir-816 Firmware

CVE-2026-4184 — Critical (CVSS 9.8): A vulnerability was detected in D-Link DIR-816 1.10CNB05. Affected by this vulnerability is an unknown functionality of…
CVE-2026-4183 — Critical (CVSS 9.8): A security vulnerability has been detected in D-Link DIR-816 1.10CNB05. Affected is an unknown function of the file…
CVE-2026-4182 — Critical (CVSS 9.8): A weakness has been identified in D-Link DIR-816 1.10CNB05. This impacts an unknown function of the file…
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