Medium severity · published Aug 6, 2026
CVE-2026-66703
WordPress MailOptin plugin <= 1.2.78.0 - Cross Site Scripting (XSS) vulnerability
6.5
CVSS
0.2%
EPSS
No
On KEV
Description
Contributor Cross Site Scripting (XSS) in MailOptin <= 1.2.78.0 versions.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
Low
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 13% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MA
MailOptin · properfraction
through 1.2.78.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-66703
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-66703
patchstack.com
https://patchstack.com/database/wordpress/plugin/mailoptin/vulnerability/wordpress-mailoptin-plugin-1-2-78-0-cross-site-scripting-xss-vulnerability?_s_id=cve
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