#VU27059 Improper Authentication in DSL-2640B - CVE-2020-9277

Vulnerability identifier: #VU27059

Vulnerability risk: Low

CVSSv4.0: 7.4 [CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/U:Clear]

CVE-ID: CVE-2020-9277

CWE-ID: CWE-287

Exploitation vector: Local network

Exploit availability: No

Vulnerable software:
DSL-2640B
Hardware solutions / Routers & switches, VoIP, GSM, etc

Vendor: D-Link

Description

The vulnerability allows a remote attacker to bypass authentication process.

The vulnerability exists due to an error when accessing cgi modules. A remote attacker on the local network can bypass authentication process and perform administrative tasks.

This vulnerability affects devices with the following versions:

• Hardware version: B2
• Firmware version: ver.4.01

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

DSL-2640B: 4.01

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External links
https://raelize.com/advisories/CVE-2020-9277_D-Link-DSL-2640B_CGI-Authentication-bypass_v1.0.txt
https://raelize.com/posts/d-link-dsl-2640b-security-advisories/
https://www.dlink.com/en/security-bulletin

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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. However, proof of concept for this vulnerability is available.