Executive brief
The Tenda W15E enterprise router, used to provide wireless connectivity and network management for small businesses, contains a security flaw in its web management interface. By sending a specially crafted web request to the device, an attacker can cause the router to crash or become unstable. This results in a denial-of-service, disrupting internet connectivity and business operations until the device is recovered.
Technical details
A stack-based buffer overflow exists in the 'formModifyWebAuthWhiteUser' function within the Tenda W15E v15.11.0.10 firmware. The vulnerability is triggered when the 'webAuthWhiteID' parameter, retrieved via 'websGetVar', is passed to 'sprintf' or 'printf' to construct MIB strings (e.g., 'portal.whiteMACList%s') without proper bounds checking. An unauthenticated attacker can exploit this by sending a crafted HTTP request to the 'modifyWebAuthWhiteUser' action with an excessively long 'webAuthWhiteID' string. Successful exploitation leads to a process crash or device instability, resulting in a Denial of Service (DoS). Preconditions include setting 'webAuthWhiteUserType' to 'mac' and ensuring other required parameters like 'webAuthWhiteUser' are present.
Affected products
- Tenda (Shenzhen Tenda Technology Co., Ltd) W15E v15.11.0.10
Timeline
- 2026-03-18: other: CVE request submitted to MITRE
- 2026-06-06: disclosed: Public disclosure of the vulnerability
- 2026-06-09: advisory: NVD published the CVE record