Improper Authorization in OptinMonster plugin for WordPress

1) Improper Authorization

EUVDB-ID: #VU57927

Risk: Medium

CVSSv3.1: 6.3 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-39341

CWE-ID: CWE-285 - Improper Authorization

Exploit availability: No

Description

The vulnerability allows a remote attacker to bypass authorization check.

The vulnerability exists due to insufficient authorization validation within the "logged_in_or_has_api_key" function in the ~/OMAPI/RestApi.php file. A remote attacker can gain access to sensitive information and update settings.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Popups by OptinMonster – Best WordPress Lead Generation Plugin: 0.9.8 - 2.6.4

External links

http://www.wordfence.com/blog/2021/10/1000000-sites-affected-by-optinmonster-vulnerabilities/
http://wordfence.com/vulnerability-advisories/#CVE-2021-39341
http://plugins.trac.wordpress.org/browser/optinmonster/trunk/OMAPI/RestApi.php?rev=2606519#L1460

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?

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