CVE-2021-39340

Public Exploit
Notification – Custom Notifications and Alerts for WordPress <= 7.2.4 Authenticated Stored Cross-Site Scripting

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.

Remediation

Solution:

  • Update to version 8.0.0, or newer.

Category

4.8
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.47%
Third-Party Advisory github.com Third-Party Advisory wordpress.org Third-Party Advisory wordfence.com
Affected: Notification – Custom Notifications and Alerts for WordPress Notification – Custom Notifications and Alerts for WordPress
Published at:
Updated at:

References

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

Frequently Asked Questions

What is the severity of CVE-2021-39340?
CVE-2021-39340 has been scored as a medium severity vulnerability.
How to fix CVE-2021-39340?
To fix CVE-2021-39340: Update to version 8.0.0, or newer.
Is CVE-2021-39340 being actively exploited in the wild?
It is possible that CVE-2021-39340 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-39340?
CVE-2021-39340 affects Notification – Custom Notifications and Alerts for WordPress Notification – Custom Notifications and Alerts for WordPress.
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