Overview
In a critical revelation, a severe vulnerability has been discovered in the D-Link DIR-600L up to version 2.07B01. This vulnerability is potentially alarming as it can lead to a buffer overflow through the manipulation of the host argument in the function formEasySetupWizard. The vulnerability is of particular significance because the attack can be initiated remotely, putting numerous systems at risk. Given the severity of the situation, understanding the intricacies of this vulnerability is crucial for organizations that may still be using these no longer supported products.
Vulnerability Summary
CVE ID: CVE-2025-4343
Severity: Critical, CVSS Severity Score 8.8
Attack Vector: Remote
Privileges Required: None
User Interaction: None
Impact: Potential system compromise or data leakage
Affected Products
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Product | Affected Versions
D-Link DIR-600L | Up to 2.07B01
How the Exploit Works
The vulnerability is present within the function formEasySetupWizard of D-Link DIR-600L. Specifically, the issue arises from the improper handling of the host argument. When manipulated, this can lead to a buffer overflow. A buffer overflow is a situation where a program or process attempts to write more data to a fixed length block of memory, or buffer, than it is allocated to hold. This overflow can overwrite adjacent memory, leading to erratic program behavior, potentially resulting in system crashes, incorrect outputs, or a breach of system security.
Conceptual Example Code
Here is a conceptual example of how an HTTP request might be manipulated to exploit this vulnerability:
POST /formEasySetupWizard HTTP/1.1
Host: target.example.com
Content-Type: application/x-www-form-urlencoded
host=AAAAAAAAAAAAAAAAAAAAAAAAAAAAA... (long string of A's to cause buffer overflow)In this example, the string of A’s represents a large amount of data that overflows the buffer when the host argument is processed. This overflowing data can potentially overwrite crucial information, leading to the aforementioned system compromise or data leakage.
Mitigation Guidance
Given that the D-Link DIR-600L products affected by CVE-2025-4343 are no longer supported by the manufacturer, it’s crucial for users to apply the appropriate vendor patch as soon as possible. If a patch is not immediately available or applicable, using a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can serve as temporary mitigation strategies. These measures can help detect and prevent attempted exploitation of the vulnerability until a more permanent solution can be implemented.