6.1

CVE-2021-39325: OptinMonster <= 2.6.0 Reflected Cross-Site Scripting

Modified
Published 20-09-2021Last modified 31-03-2025

Vulnerability summary

CVE-2021-39325 is a medium (CVSS 6.1) Cross-site Scripting vulnerability in optinmonster. EPSS estimates a 0.91% chance of exploitation in the next 30 days, higher than 59.4% of scored vulnerabilities. Fixed in 2.6.1.

Overall risk
25/100
0100
Medium · default modelHow is this calculated?
CVSS score
6.1/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.91%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Timeline

  1. 20-09-2021
    PublishedVulnerability first disclosed.
  2. 31-03-2025
    Last modifiedVulnerability information updated.

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 metrics

4 scores · 3 sources · 2 versions

EPSS trend

Probability

0.91%

Chance of exploitation in the next 30 days

Percentile

59%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.91% on 22-09-2026

22-09-202622-10-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Optinmonster1 product
Wordpress1 product
  • optinmonster≤ 2.6.0 (fixed in 2.6.1)

2 vendors · 2 products

References

3 links