What’s Vulnerable › Vulnerabilities

CVE-2021-39340: Notification – Custom Notifications and Alerts for WordPress <= 7.2.4 Authenticated Stored Cross-Site Scripting

• Severity: low (CVSS 2.1 v2.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.9% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2021-11-01 · updated 2026-06-17
• Weakness: CWE-79

Description

The Notification WordPress plugin is vulnerable to Stored Cross-Site Scripting due to insufficient input validation and sanitization via several parameters found in the ~/src/classes/Utils/Settings.php file which made it possible for attackers with administrative user access to inject arbitrary web scripts, in versions up to and including 7.2.4. This affects multi-site installations where unfiltered_html is disabled for administrators, and sites where unfiltered_html is disabled.

Affected products

• Notification – Custom Notifications and Alerts for WordPress: through 7.2.4

References

• https://github.com/BigTiger2020/word-press/blob/main/Notification.md
• https://plugins.trac.wordpress.org/browser/notification/tags/7.2.4/src/classes/Utils/Settings.php#L167
• https://wordfence.com/vulnerability-advisories/#CVE-2021-39340
• https://github.com/BigTiger2020/word-press/blob/main/Notification.md
• https://plugins.trac.wordpress.org/browser/notification/tags/7.2.4/src/classes/Utils/Settings.php#L167
• https://wordfence.com/vulnerability-advisories/#CVE-2021-39340

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