Overview
A severe vulnerability has been discovered in D-Link DI-8100 version 1.0, a popular networking hardware device. This vulnerability has been classified as critical, posing a significant risk to all systems running this version of the device. It pertains to the function ‘sprintf’ in the file ‘/upnp_ctrl.asp’ of the component ‘jhttpd’. This vulnerability could allow a remote attacker to manipulate ‘remove_ext_proto/remove_ext_port’ arguments, leading to a stack-based buffer overflow. Given its potential to compromise systems and lead to data leakage, it is imperative that organizations take immediate steps to patch their systems or implement appropriate mitigations.
Vulnerability Summary
CVE ID: CVE-2025-7911
Severity: Critical, CVSS Score 8.8
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: Potential system compromise or data leakage
Affected Products
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Product | Affected Versions
D-Link DI-8100 | 1.0
How the Exploit Works
The vulnerability lies in the sprintf function of the file /upnp_ctrl.asp of the jhttpd component. An attacker can remotely manipulate the arguments remove_ext_proto/remove_ext_port to induce a stack-based buffer overflow. This overflow can allow the attacker to execute arbitrary code on the system, potentially compromising the system or leading to data leakage.
Conceptual Example Code
The following is a conceptual example of how the vulnerability might be exploited using a HTTP request.
POST /upnp_ctrl.asp HTTP/1.1
Host: vulnerable_device_IP
Content-Type: application/json
{
"remove_ext_proto": "OVERFLOWING STRING HERE",
"remove_ext_port": "OVERFLOWING STRING HERE"
}In the above example, the attacker sends a POST request with overly-long strings as values for remove_ext_proto and remove_ext_port, causing a buffer overflow in the host device’s memory.
Mitigation Guidance
The best course of action to mitigate this vulnerability is to apply the vendor-provided patch. If the patch cannot be applied immediately, using a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can serve as temporary mitigation. These systems can be configured to detect and block attempts to exploit this vulnerability. However, these are only temporary solutions and should be replaced with the vendor patch as soon as feasible.