CVE-2021-39325 json
OptinMonster <= 2.6.0 Reflected Cross-Site Scripting
published 2021-09-20 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-25686
- cvss
- 6.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.9%
- EPSS 0.9% chance of exploitation in 30 days, percentile 60%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 19 mo ago
Exploit prediction
0.91% chance of exploitation in the next 30 days, higher than 60% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| NVD | 2.0 | 4.3 | AV:N/AC:M/Au:N/C:N/I:P/A:N |
Affected products
- OptinMonster OptinMonster
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
- Technology feeds
References
-
plugins.trac.wordpress.org
/changeset?sfp_email=&sfph_mail=&reponame=&old=2595758%40optinmonster&new=2595758%40optinmonster&sfp_email=&sf
patch, third-party-advisory
-
wordfence.com
/vulnerability-advisories/#CVE-2021-39325
third-party-advisory
Sources
- CVE List CVE-2021-39325
- NVD CVE-2021-39325
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.