Author: Ameeba

Overview

The cybersecurity landscape is fraught with various kinds of vulnerabilities, one of which is the CVE-2025-7913. Classified as critical, this vulnerability affects the TOTOLINK T6 4.1.5cu.748_B20211015. It exposes the MQTT Service’s function updateWifiInfo to manipulation of the argument serverIp that leads to a buffer overflow. The vulnerability is of critical importance as it allows an attacker to remotely launch an attack, potentially compromising the system or leading to data leakage.

Vulnerability Summary

CVE ID: CVE-2025-7913
Severity: Critical (8.8 CVSS Severity Score)
Attack Vector: Remote via Network
Privileges Required: None
User Interaction: None
Impact: Potential system compromise or data leakage

Affected Products

Product | Affected Versions

TOTOLINK T6 | 4.1.5cu.748_B20211015

How the Exploit Works

The vulnerability resides in the MQTT Service’s function updateWifiInfo. The function’s argument serverIp can be manipulated in such a way that it causes a buffer overflow. This is essentially an anomaly where a program, while writing data to a buffer, overruns the buffer’s boundary and overwrites adjacent memory locations. This overrun could be exploited to inject malicious code into the system, execute arbitrary code, or even crash the system.

Conceptual Example Code

Below is a conceptual example of how the vulnerability might be exploited. It represents how a malformed packet could be sent to the serverIp argument to trigger the buffer overflow:

POST /updateWifiInfo HTTP/1.1
Host: target.example.com
Content-Type: application/json
{ "serverIp": "A long string that overflows the buffer..." }

This example is not a working exploit, but serves to illustrate the type of input that an attacker might use to exploit the vulnerability.

Mitigation and Prevention

The most effective way to mitigate this vulnerability is to apply the vendor patch as soon as it is available. In the meantime, using a Web Application Firewall (WAF) or an Intrusion Detection System (IDS) could provide temporary protection. These systems can help to identify and block potentially malicious traffic. Regular security audits and software updates are also highly recommended to prevent future vulnerabilities.

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

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.

Overview

A critical vulnerability, tagged as CVE-2025-7910, has been identified in D-Link DIR-513 routers version 1.10. This vulnerability is of significant concern as it affects the function sprintf of the file /goform/formSetWanNonLogin of the Boa Webserver component. The vulnerability could be exploited remotely, and the exploit has been publicly disclosed, making the affected systems a potential target for cybercriminals. Given the criticality of this vulnerability, it is crucial for users and administrators to understand the risks involved and take necessary precautions.

Vulnerability Summary

CVE ID: CVE-2025-7910
Severity: Critical (8.8 CVSS Score)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: Potential system compromise and data leakage

Affected Products

Product | Affected Versions

D-Link DIR-513 | 1.10

How the Exploit Works

The vulnerability emanates from an incorrect use of the sprintf function in the file /goform/formSetWanNonLogin of the Boa Webserver component, leading to a stack-based buffer overflow. This vulnerability is triggered when an excessively long ‘curTime’ argument is passed, causing the stack buffer to overflow. This overflow can be exploited by an attacker to execute arbitrary code or potentially compromise the system’s integrity and confidentiality.

Conceptual Example Code

Here is a
conceptual
example of how the vulnerability could be exploited using an HTTP request:

POST /goform/formSetWanNonLogin HTTP/1.1
Host: target.example.com
Content-Type: application/x-www-form-urlencoded
curTime=AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA...

In the above example, an excessively long ‘curTime’ argument is sent to the server, leading to a buffer overflow.

Mitigation and Recommendations

Affected users are advised to apply the vendor’s patch to correct this vulnerability. As this vulnerability affects products that are no longer supported by the maintainer, users are encouraged to upgrade to a newer, supported version of the product. In the meantime, a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can be used as a temporary mitigation strategy. These systems can detect and prevent exploitation attempts targeting this vulnerability.

Overview

In the cybersecurity landscape, vulnerabilities are regularly discovered in both current and legacy systems. One such recent discovery is CVE-2025-7909, a critical vulnerability found in the D-Link DIR-513 1.0 router. This vulnerability has been rated as critical due to its potential to compromise systems and lead to significant data leakage. It specifically impacts the Boa Webserver component of these routers, which are no longer supported by D-Link. This lack of support increases the risk, as users cannot rely on vendor patches or updates for mitigation.

Vulnerability Summary

CVE ID: CVE-2025-7909
Severity: Critical (CVSS Score: 8.8)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: Potential system compromise and data leakage

Affected Products

Product | Affected Versions

D-Link DIR-513 | 1.0

How the Exploit Works

The vulnerability resides in the sprintf function of the file /goform/formLanSetupRouterSettings of the Boa Webserver component. The issue is triggered by improper handling of the argument ‘curTime’. An attacker can manipulate the ‘curTime’ argument, leading to a stack-based buffer overflow. This overflow can allow unauthorized remote execution of arbitrary code. This vulnerability is particularly dangerous because it can be exploited remotely, and the exploit has been publicly disclosed.

Conceptual Example Code

Here is a conceptual example of how the vulnerability might be exploited. It entails issuing a HTTP request with a manipulated ‘curTime’ argument in the payload:

POST /goform/formLanSetupRouterSettings HTTP/1.1
Host: target_router_ip
Content-Type: application/x-www-form-urlencoded
curTime=AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA...

In this example, ‘A’s represent an excessively long string which would cause a buffer overflow in the target router’s memory stack.

Mitigation Guidance

In the absence of an official patch from the vendor, users can mitigate the risk by employing a Web Application Firewall (WAF) or Intrusion Detection System (IDS) to detect and block attempts to exploit the vulnerability. It is also advisable to replace unsupported devices like the D-Link DIR-513 1.0 with newer, supported models to ensure ongoing security updates and protection.

Overview

A critical vulnerability has been discovered in D-Link DI-8100 1.0, which could potentially lead to a system compromise or data leakage. This vulnerability lies within the sprintf function of the jhttpd component, specifically in the /ddns.asp?opt=add file. The vulnerability has been assigned a severity score of 8.8 (CVSS), making it a critical concern for all users of the affected product. It is of utmost importance that necessary measures are taken to mitigate the risks associated with this vulnerability.
In this blog post, we will delve into the details of this vulnerability, understand how it works, and explore the mitigation strategies.

Vulnerability Summary

CVE ID: CVE-2025-7908
Severity: Critical, CVSS Score 8.8
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: Potential system compromise or data leakage

Affected Products

Product | Affected Versions

D-Link DI-8100 | 1.0

How the Exploit Works

The vulnerability stems from the improper handling of the ‘mx’ argument in the sprintf function of the /ddns.asp?opt=add file. Specifically, by manipulating this ‘mx’ argument, an attacker can cause a stack-based buffer overflow. This could potentially allow the attacker to execute arbitrary code or disrupt the normal operation of the affected system. This attack can be launched remotely and does not require any user interaction, making it a severe threat.

Conceptual Example Code

Here’s a conceptual example of how an HTTP request exploiting this vulnerability might look like:

POST /ddns.asp?opt=add HTTP/1.1
Host: target.example.com
Content-Type: application/x-www-form-urlencoded
mx=%s [Repeated long enough to overflow the buffer]

In the above example, the ‘%s’ is repeated long enough to overflow the buffer, potentially allowing an attacker to execute arbitrary code.

Mitigation

The most effective way to mitigate this vulnerability is to apply the patch provided by the vendor. If the patch cannot be applied immediately, using a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can serve as a temporary mitigation strategy. These systems can help identify and block potential exploit attempts. However, it is highly recommended to apply the vendor patch as soon as possible to fully protect the system from this vulnerability.
Remember, staying vigilant and proactive in applying patches and updates is key in maintaining a strong security posture.