#VU56414 Improper access control in Zoho ManageEngine ADSelfService Plus - CVE-2021-40539

Vulnerability identifier: #VU56414

Vulnerability risk: Critical

CVSSv4.0: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Red]

CVE-ID: CVE-2021-40539

CWE-ID: CWE-284

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
Zoho ManageEngine ADSelfService Plus
Client/Desktop applications / Software for system administration

Vendor: Zoho Corporation

Description

The vulnerability allows a remote attacker to compromise the affected system.

The vulnerability exists due to improper access restrictions to the "/RestAPI/LogonCustomization" and "/RestAPI/Connection" REST API endpoints. A remote non-authenticated attacker can send specially HTTP requests to the aforementioned REST API endpoints and execute arbitrary code on the system.

Note, the vulnerability is being actively exploited in the wild.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Zoho ManageEngine ADSelfService Plus: 6000 - 6113

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External links
https://www.manageengine.com/products/self-service-password/kb/how-to-fix-authentication-bypass-vulnerability-in-REST-API.html

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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 Internet.

Is there known malware, which exploits this vulnerability?

Yes. This vulnerability is being exploited in the wild.