A new security flaw, CVE-2024-51138, has been identified in various versions of Vigor routers, including Vigor165/166 4.2.7 and earlier; Vigor262/LTE200 3.9.8.9 and earlier; Vigor286/2925 3.9.8 and earlier; Vigor2862/2926 3.9.9.5 and earlier; Vigor2133/2762/2832 3.9.9 and earlier; Vigor2135/2765/2766 4.4.5. and earlier; Vigor2865/2866/2927 4.4.5.3 and earlier; Vigor2962 4.3.2.8 and earlier; Vigor3912 4.3.6.1 and earlier; Vigor391 4.4.3.1 and earlier. This security vulnerability is a result of stack-based buffer overflow in the URL parsing functionality of the TR069 STUN server.

In this post, we will dive into the details of this vulnerability, providing examples of how it can be exploited and links to original references.

Exploit Details

The vulnerability arises due to insufficient bounds checking on the amount of URL parameters in the TR069 STUN server's URL parsing functionality. This buffer overflow vulnerability enables a remote attacker to exploit the overflow by sending a maliciously crafted request.

An example of a code snippet showcasing this vulnerability

void parse_url(char *url) {
  char buffer[256];
  int i = ;

  while (*url != '\' && i < 256) {
    buffer[i] = *url;
    url++;
    i++;
  }
  buffer[i] = '\';

  // URL processing logic ...
}

By sending a maliciously crafted request, an attacker can cause the buffer to overflow, potentially executing arbitrary code with elevated privileges on the targeted system.

1. Official CVE Details: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2024-51138

2. Vigor Router Product Page: https://www.vigor-router.com/

3. TR069 Standard: https://www.broadband-forum.org/technical/download/TR-069_Amendment-5.pdf

1. Update to the latest firmware version available for Vigor routers, which can be downloaded from the official product page https://www.vigor-router.com/.

2. Restrict the access of the TR069 STUN server from untrusted networks; this may include implementing firewall rules, access control lists or other security controls to prevent unauthorized access.

3. Monitor network traffic for any suspicious activity, and promptly report any potential attempts to exploit this vulnerability to your network administrator or vendor support team.

Conclusion

CVE-2024-51138 is a critical security vulnerability affecting multiple versions of Vigor routers. By exploiting this stack-based buffer overflow vulnerability, a remote attacker can potentially execute arbitrary code with elevated privileges. Users of Vigor routers should take immediate action to update their firmware to the latest version, as well as implementing security best practices to mitigate the risks associated with this vulnerability.

Timeline

Published on: 02/27/2025 21:15:37 UTC
Last modified on: 02/28/2025 22:15:39 UTC