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CVE-2021-39341

Status: ModifiedHigh (8.2)—Exploit
Severity8.2High · CVSS 3.1
Exploitation probability22 %higher than 98% of CVEs
Active exploitationNonot in the CISA catalog
Public exploitAvailableNuclei template (automated mass detection)

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

Base score
8.2
Version
3.1
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days
22 %
Percentile among all scored CVEs
98
Score date
10/27/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Public exploits

Exploit code or detection templates are publicly available. This is not the same as confirmed active exploitation (KEV), but it raises the risk: patch with priority.

Affected technologies (1)

Optinmonster — Optinmonster

CWEs

References

Show 6 references

Raw JSON (NVD)

Show
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  "lastModified": "2026-06-17T04:03:34.893",
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