VDB
CVE-2026-11405
CVE-2026-11405
PUBLISHED
CVSS 9.8 CRITICAL
Reported by certcc · Published July 6, 2026
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
Risk Scores
CVSS 3.1
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Tenda | firmware | US_AC6V2.0RTL_V15.03.06.51_multi_T |
| Tenda | firmware | US_AC5V1.0RTL_V15.03.06.48_multi_TDE01 |
| Tenda | firmware | US_AC10V1.0re_V15.03.06.46_multi_TDE01 |
| Tenda | firmware | US_W15EV1.0br_V15.11.0.5(1068_1567_841)_EN_TDE |
| Tenda | firmware | US_FH1201V1.0BR_V1.2.0.14(408)_EN_TD |
| Tenda | firmware | US_AC6V2.0RTL_V15.03.06.51_multi_T, US_AC5V1.0RTL_V15.03.06.48_multi_TDE01, US_AC10V1.0re_V15.03.06.46_multi_TDE01 |
Timeline
- Jul 6, 2026 CVE Published
- Jul 7, 2026 EPSS Score
- Jul 7, 2026 Coalition ESS Score
- Jul 8, 2026 Security Advisory
- Jul 8, 2026 CVE Updated