CVE-2021-34666: Add Sidebar <= 2.0.0 Reflected Cross-Site Scripting

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.8% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2021-08-16 · updated 2026-06-17
Weakness: CWE-79

Description

The Add Sidebar WordPress plugin is vulnerable to Reflected Cross-Site Scripting via the add parameter in the ~/wp_sidebarMenu.php file which allows attackers to inject arbitrary web scripts, in versions up to and including 2.0.0.

Affected products

Add Sidebar: through 2.0.0

References

https://plugins.trac.wordpress.org/browser/sidebar-adder/tags/2.0.1/wp_sidebarMenu.php#L124
https://www.wordfence.com/vulnerability-advisories/#CVE-2021-34666
https://plugins.trac.wordpress.org/browser/sidebar-adder/tags/2.0.1/wp_sidebarMenu.php#L124
https://www.wordfence.com/vulnerability-advisories/#CVE-2021-34666

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