High severity · published Nov 1, 2021
CVE-2021-39341
OptinMonster <= 2.6.4 Unprotected REST-API Endpoints
8.2
CVSS
21.9%
EPSS
No
On KEV
Description
The OptinMonster WordPress plugin is vulnerable to sensitive information disclosure and unauthorized setting updates due to insufficient authorization validation via the logged_in_or_has_api_key function in the ~/OMAPI/RestApi.php file that can used to exploit inject malicious web scripts on sites with the plugin installed. This affects versions up to, and including, 2.6.4.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)21.9% · higher than 98% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OP
OptinMonster · OptinMonster
2.6.4 through 2.6.4 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-39341
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-39341
Third Party Advisory
https://plugins.trac.wordpress.org/browser/optinmonster/trunk/OMAPI/RestApi.php?rev=2606519#L1460
Third Party Advisory
https://wordfence.com/vulnerability-advisories/#CVE-2021-39341
Exploit
https://www.wordfence.com/blog/2021/10/1000000-sites-affected-by-optinmonster-vulnerabilities/
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