A recent vulnerability, identified as CVE-2023-44020, has been discovered in the Tenda AC10U v1. US_AC10UV1.RTL_V15.03.06.49_multi_TDE01 firmware. The issue lies in a stack overflow that is triggered by the security parameter within the formWifiBasicSet function. This post will provide an in-depth analysis of the vulnerability, including the affected code snippet, original references, and exploit details.

Affected Code Snippet

The vulnerability is present in the formWifiBasicSet function, which is responsible for setting up the basic Wi-Fi configuration. The problem occurs when an attacker sends an overly large input for the security parameter, leading to a stack overflow. Below is a simplified code snippet demonstrating the vulnerability:

void formWifiBasicSet(char *security) {
    char security_buffer[64];

    strcpy(security_buffer, security);
    // ... other processing ...
}

Original References

The discovery of CVE-2023-44020 can be attributed to the security research community, and the findings have been shared through various reports and advisories. Here are some original references detailing the vulnerability:

1. CVE-2023-44020 Official CVE Entry: The official Common Vulnerabilities and Exposures (CVE) entry for this vulnerability offers a brief description and affected versions.
2. Security Advisory on Tenda AC10U Stack Overflow Vulnerability: This security advisory provides more technical details about the vulnerability and its exploit potential.
3. GitHub Repository with Proof-of-Concept Exploit: A GitHub repository that hosts a proof-of-concept exploit for the vulnerability, demonstrating its real-world impact.

Exploit Details

An attacker who takes advantage of the stack overflow vulnerability can potentially execute arbitrary code on the affected router, leading to full system compromise. The exploitation process generally involves the following steps:

1. Craft a malicious request with an overly long string for the security parameter (e.g., 257 or more bytes long).
2. Send the request to the target Tenda AC10U router, causing it to process the formWifiBasicSet function with the injected value.

Mitigation and Patch

To protect against exploitation of CVE-2023-44020, it is essential for those using the affected firmware to apply the latest updates from Tenda. The manufacturer has released patched firmware versions that address the stack overflow vulnerability:

- Tenda AC10U Firmware Update: The firmware section of Tenda's official website provides the most recent firmware updates for all supported models, including the AC10U.

Conclusion

CVE-2023-44020 highlights the significance of secure programming practices and thorough testing of networking devices. This stack overflow vulnerability in Tenda AC10U v1. US_AC10UV1.RTL_V15.03.06.49_multi_TDE01 allows an attacker to execute arbitrary code and gain full control over the router. It is critical for affected users to apply the patched firmware to mitigate the risk of exploitation.

Timeline

Published on: 09/27/2023 15:19:35 UTC
Last modified on: 09/27/2023 18:45:01 UTC