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Vulnerability record · CVE-2021-39325 · published 20 September 2021

CVE-2021-39325: Optinmonster cross-site scripting vulnerability

Optinmonster · Optinmonster

The OptinMonster WordPress plugin is vulnerable to Reflected Cross-Site Scripting due to insufficient input validation in the load_previews function found in the ~/OMAPI/Output.php file which allows attackers to inject arbitrary web scripts, in versions up to and including 2.6.0.

6.1 CVSS 3.1 Medium EPSS 0.91% · top 41.8% CWE-79 · Cross-site scripting
6.1CVSS 3.1 base score, v2 4.3
0.91%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
4References
17 Jun 2026Last modified by NVD

Description

The OptinMonster WordPress plugin is vulnerable to Reflected Cross-Site Scripting due to insufficient input validation in the load_previews function found in the ~/OMAPI/Output.php file which allows attackers to inject arbitrary web scripts, in versions up to and including 2.6.0.

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&old=2595758%40optinmonster&new=2595758%40op PatchThird Party Advisory
https://www.wordfence.com/vulnerability-advisories/#CVE-2021-39325 Third Party Advisory
https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&old=2595758%40optinmonster&new=2595758%40op PatchThird Party Advisory
https://www.wordfence.com/vulnerability-advisories/#CVE-2021-39325 Third Party Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2021-39325), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.