Hidden backdoor authentication mechanism in multiple versions of Tenda firmware allows admin access to web management interface
48Vexday Risk Score
No sign of exploitation. It has a public proof of concept.
ssvc Attendcvss 9.8epss 0.8%
from disclosure to weapon1 days
Published on NVDJul 6
1st PoC+1d
exploitation probability
0.8%top 48% of all CVEs
observed exploitation
nono source reports it
1 public exploit(s)
The web server binary /bin/httpd contains a hidden backdoor authentication mechanism in the login() function at 004c88b8.
- The function contains a normal authentication path using MD5/hash-based password verification (prod_encode64/PasswordToMd5/check_rand_key).
- After normal authentication fails, it calls GetValue("sys.rzadmin.password") to read a backdoor password from the device configuration.
- It performs a direct strcmp() comparison (plaintext, not hashed) between the config value and the user-supplied password.
A successful match grants role=2 (admin-level access) and creates a valid session. The rzadmin username is never checked — any username works with the backdoor
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
Tenda · firmwarepublic PoCs found — 1
githubgithub.com/HORKimhab/CVE-2026-11405★ 0⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.