#VU69569 Use of insufficiently random values in TL-WR940N - CVE-2022-43636

Vulnerability identifier: #VU69569

Vulnerability risk: Medium

CVSSv4.0: 5.2 [CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2022-43636

CWE-ID: CWE-330

Exploitation vector: Local network

Exploit availability: No

Vulnerable software:
TL-WR940N
Hardware solutions / Routers for home users

Vendor: TP-Link

Description

The vulnerability allows a remote attacker to bypass authentication process.

The vulnerability exists due to the lack of sufficient randomness in the sequnce numbers used for session managment within the httpd service. A remote attacker on the local network can bypass authentication process and gain unauthorized access to the application.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

TL-WR940N: before 6_3.20.1 Build 220801

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External links
https://www.zerodayinitiative.com/advisories/ZDI-22-1614/

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.