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Status published
Medium
CVE-2021-24153
Yoast SEO < 3.4.1 - Authenticated Stored Cross-Site Scripting (XSS)
Vulnerability Description
A Stored Cross-Site Scripting vulnerability was discovered in the Yoast SEO WordPress plugin before 3.4.1, which had built-in blacklist filters which were blacklisting Parenthesis as well as several functions such as alert but bypasses were found.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:
- Hammad Shamsi
References
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Affected Vendor
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View all reports →Affected Software
Yoast SEO
Vulnerable Versions:
3.4.1
Timeline
Official Publish:
April 5th, 2021
Last Modified:
August 3rd, 2024
Added to House:
July 21st, 2026
CVSS Vectors
V3:
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N