CVE-2026-11405
Hidden backdoor authentication mechanism in multiple versions of Tenda firmware allows admin access to web management interface
Description
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
INFO
Published Date :
July 6, 2026, 8:16 p.m.
Last Modified :
July 6, 2026, 8:16 p.m.
Remotely Exploit :
No
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-11405
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
Solution
- Remove the backdoor password configuration.
- Rebuild the web server binary without the backdoor.
- Deploy the updated web server binary.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-11405.
| URL | Resource |
|---|---|
| https://cwe.mitre.org/data/definitions/912.html | |
| https://kb.cert.org/vuls/id/213560 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-11405 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-11405
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-11405 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-11405 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Jul. 06, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'Tenda', 'product': 'firmware', 'versions': [{'status': 'affected', 'version': 'US_AC6V2.0RTL_V15.03.06.51_multi_T'}]}, {'vendor': 'Tenda', 'product': 'firmware', 'versions': [{'status': 'affected', 'version': 'US_AC5V1.0RTL_V15.03.06.48_multi_TDE01'}]}, {'vendor': 'Tenda', 'product': 'firmware', 'versions': [{'status': 'affected', 'version': 'US_AC10V1.0re_V15.03.06.46_multi_TDE01'}]}, {'vendor': 'Tenda', 'product': 'firmware', 'versions': [{'status': 'affected', 'version': 'US_W15EV1.0br_V15.11.0.5(1068_1567_841)_EN_TDE'}]}, {'vendor': 'Tenda', 'product': 'firmware', 'versions': [{'status': 'affected', 'version': 'US_FH1201V1.0BR_V1.2.0.14(408)_EN_TD'}]}] Added Description 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 Added Reference https://cwe.mitre.org/data/definitions/912.html Added Reference https://kb.cert.org/vuls/id/213560