PT-2022-12689 · Tenda · Tenda Ax3

Published 2022-03-04 · Updated 2022-03-10 · CVE-2021-46394

Positive Technologies (AI Summary)

CVSS v3.1

9.8

Critical

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions Tenda-AX3 router version V16.03.12.10 CN

Description The issue is related to a stack buffer overflow vulnerability in the formSetPPTPServer function. The v13 variable is directly retrieved from the HTTP request parameter startIp without any security checks, and then it is passed to the stack by the sscanf function, causing a stack overflow. This can be exploited by sending a POST request to the "/goform/SetPptpServerCfg" API endpoint with a carefully crafted startIp parameter, allowing for remote code execution.

Recommendations For Tenda-AX3 router version V16.03.12.10 CN, as a temporary workaround, consider disabling the formSetPPTPServer function until a patch is available. Restrict access to the "/goform/SetPptpServerCfg" API endpoint to minimize the risk of exploitation. Avoid using the startIp parameter in the affected API endpoint until the issue is resolved. At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Exploit

Memory Corruption

Weakness Enumeration

CWE-787

Related Identifiers

CVE-2021-46394

Affected Products

Tenda Ax3

References · 5

• 🔥 https://github.com/sec-bin/IoT-CVE/tree/main/Tenda/AX3/4 · Exploit
• https://osv.dev/vulnerability/CVE-2021-46394 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2021-46394 · Security Note
• https://t.me/cibsecurity/38412 · Telegram Post
• https://t.me/cvenotify/27756 · Telegram Post