Overview
The cybersecurity landscape continues to evolve with new vulnerabilities constantly being discovered. One of these is the CVE-2025-45843 vulnerability, an authenticated stack overflow found in the TOTOLINK NR1800X router firmware version V9.1.0u.6681_B20230703. This vulnerability could potentially compromise systems and lead to data leakage, posing a serious risk to users of the affected product.
The issue lies in the ssid parameter of the setWiFiGuestCfg function. If exploited, it could lead to unauthorized access and control over the system. This is a critical concern for users and administrators of TOTOLINK NR1800X routers, especially those managing sensitive data on their networks.
Vulnerability Summary
CVE ID: CVE-2025-45843
Severity: High (CVSS: 8.8)
Attack Vector: Network
Privileges Required: Low
User Interaction: Required
Impact: System compromise, potential data leakage.
Affected Products
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Product | Affected Versions
TOTOLINK NR1800X | V9.1.0u.6681_B20230703
How the Exploit Works
The vulnerability in the TOTOLINK NR1800X firmware is due to an authenticated stack overflow in the setWiFiGuestCfg function. This function fails to properly verify the ssid parameter for size before copying it into a fixed-length buffer on the stack. An attacker can exploit this flaw by sending a specially crafted request with an oversized ssid parameter, causing a buffer overflow.
Conceptual Example Code
Below is a conceptual example of how an attacker might exploit this vulnerability:
POST /setWiFiGuestCfg HTTP/1.1
Host: target.example.com
Authorization: Basic [Base64-encoded credentials]
Content-Type: application/json
{ "ssid": "<malicious oversized string>" }In this example, the attacker would replace `
Mitigation
The immediate mitigation for this vulnerability is to apply the vendor’s patch once it becomes available. As a temporary solution, users and administrators can employ Web Application Firewall (WAF) or Intrusion Detection Systems (IDS) to detect and prevent any malicious activities related to this exploit. Regular monitoring and updating of systems are always recommended to ensure that all potential vulnerabilities are addressed promptly.