CVE-2026-66703 MEDIUM

CVE-2026-66703: WordPress MailOptin plugin <= 1.2.78.0 - Cross Site Scripting (XSS) vulnerability

Vendor Properfraction

Product MailOptin

Weakness CWE-79 · XSS

Published August 6, 2026

Last update August 6, 2026

View on NVD All CVEs

CVSS base score

6.5/10

Attack vector Network

Attack complexity Low

Privileges required Low

User interaction Required

Confidentiality Low

Integrity Low

CVSS vector

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

What the vulnerability does

01Description

Contributor Cross Site Scripting (XSS) in MailOptin <= 1.2.78.0 versions.

Explanation of Vulnerability in Simple Terms

02Summary

MailOptin versions up to 1.2.78.0 contain a cross-site scripting vulnerability that allows authenticated users to inject malicious scripts. An attacker with low-level access can craft a request that executes JavaScript in other users' browsers, potentially compromising accounts or stealing data. The vulnerability requires user interaction and affects the scope beyond the vulnerable component.

What an attacker can do

03Attacker Capabilities

Inject and execute JavaScript code in other users' browsers to steal data or compromise accounts.

Potential impact on your site

04Site Impact

Authenticated users' sessions and data can be compromised if they interact with attacker-controlled content.

Conditions required to exploit

05Prerequisites

Attacker needs a low-privilege account and must trick a user into visiting a malicious link or page.

Key dates

06Disclosure timeline

August 6, 2026 CVE published

August 6, 2026 Record updated

External resources

07References

NVD — National Vulnerability Database https://nvd.nist.gov/vuln/detail/CVE-2026-66703 CWE — Common Weakness Enumeration https://cwe.mitre.org/data/definitions/79.html AskarLabs — CWE-79 write-up Cross-Site Scripting

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