Cyber Posture

CVE-2026-4183

CriticalPublic PoC

Published: 16 March 2026

Published
16 March 2026
Modified
19 March 2026
KEV Added
Patch
CVSS Score 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0027 50.8th percentile
Risk Priority 20 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-4183 is a critical-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Dlink Dir-816 Firmware. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 49.2% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified are NIST 800-53 SA-22 (Unsupported System Components) and SC-7 (Boundary Protection).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190). What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

Mandates replacement or retirement of unsupported end-of-life system components like the D-Link DIR-816 router, directly eliminating exposure to this unpatchable vulnerability.

prevent

Prevents stack-based buffer overflows by enforcing validation of critical inputs such as the pskValue argument in the vulnerable CGI script.

prevent

Blocks remote unauthenticated network access to the goahead web server component hosting the vulnerable /goform/form2WlanBasicSetup.cgi endpoint.

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Why these techniques?

The vulnerability is a remotely exploitable buffer overflow in the public-facing web interface (CGI script) of a router's goahead web server, directly enabling arbitrary code execution via T1190: Exploit Public-Facing Application.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

NVD Description

A security vulnerability has been detected in D-Link DIR-816 1.10CNB05. Affected is an unknown function of the file /goform/form2WlanBasicSetup.cgi of the component goahead. Such manipulation of the argument pskValue leads to stack-based buffer overflow. The attack can be executed remotely.…

more

The exploit has been disclosed publicly and may be used. This vulnerability only affects products that are no longer supported by the maintainer.

Deeper analysisAI

CVE-2026-4183 is a stack-based buffer overflow vulnerability (CWE-119, CWE-121, CWE-787) affecting the D-Link DIR-816 router on firmware version 1.10CNB05. The flaw exists in an unknown function of the file /goform/form2WlanBasicSetup.cgi within the goahead web server component, where manipulation of the pskValue argument triggers the overflow. Published on 2026-03-16, it carries a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), indicating critical severity.

Any remote unauthenticated attacker can exploit this vulnerability over the network with low complexity and no user interaction. Successful exploitation allows arbitrary code execution, potentially granting full control over the device, including data exfiltration, modification of configurations, or denial of service.

VulDB advisories and a GitHub disclosure detail the vulnerability, confirming public availability of an exploit. The affected products are no longer supported by D-Link, so no patches or firmware updates are available; mitigation relies on isolating exposed devices, restricting network access, or decommissioning them. The general D-Link website provides no specific guidance for this issue.

Details

CWE(s)

Affected Products

dlink
dir-816 firmware
1.10cnb05

CVEs Like This One

CVE-2026-4184Same product: Dlink Dir-816
CVE-2026-4182Same product: Dlink Dir-816
CVE-2026-4181Same product: Dlink Dir-816
CVE-2026-8346Same product: Dlink Dir-816
CVE-2024-57684Same product: Dlink Dir-816
CVE-2026-4180Same product: Dlink Dir-816
CVE-2025-60679Same product: Dlink Dir-816
CVE-2026-8344Same product: Dlink Dir-816
CVE-2026-8345Same product: Dlink Dir-816
CVE-2026-4211Same vendor: Dlink

References