CVE-2022-43636: TP-Link TL-WR940N httpd Use of Insufficiently Random Values Authentication Bypass Vulnerability

Published Mar 29, 2023
·
Updated

This vulnerability allows network-adjacent attackers to bypass authentication on affected installations of TP-Link TL-WR940N 6211111 3.20.1(US) routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the httpd service, which listens on TCP port 80 by default. The issue results from the lack of sufficient randomness in the sequnce numbers used for session managment. An attacker can leverage this vulnerability to bypass authentication on the system. Was ZDI-CAN-18334.

Other sources

This vulnerability allows network-adjacent attackers to bypass authentication on affected installations of TP-Link TL-WR940N routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the httpd service, which listens on TCP port 80 by default. The issue results from the lack of sufficient randomness in the sequnce numbers used for session managment. An attacker can leverage this vulnerability to bypass authentication on the system.

Affected Software

3 affected components
TP-Link TL-WR940N
TP-Link Tl-wr940n Firmware=6_211111_3.20.1
TP-Link TL-WR940N

Event History

Mar 29, 2023
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
DescriptionSeverityWeakness
Mar 24, 2025
Advisory Published
via ZDI·03:10 PM

Frequently Asked Questions

1

What is the vulnerability ID for this TP-Link TL-WR940N vulnerability?

The vulnerability ID for this TP-Link TL-WR940N vulnerability is CVE-2022-43636.

2

What is the severity of CVE-2022-43636?

CVE-2022-43636 has a severity rating of 8.8 (High).

3

How can an attacker exploit CVE-2022-43636?

Network-adjacent attackers can exploit CVE-2022-43636 to bypass authentication on affected installations of TP-Link TL-WR940N routers.

4

Do I need authentication to exploit CVE-2022-43636?

No, authentication is not required to exploit CVE-2022-43636.

5

Is there a fix available for CVE-2022-43636?

At the time of writing, no specific fix information is available for CVE-2022-43636. It is recommended to follow the provided reference for any updates or patches.

Contact

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