Threat intelligence

Yoast SEO <= 27.1.1 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'jsonText' Block Attribute

CVE-2026-3427 · wordpress-seo

Important: Seeing this vulnerability listed does not mean your website is affected. Exposure depends on whether you run Wordpress Seo at a vulnerable version. How SiteRespond intelligence works

Vulnerability: Yoast SEO <= 27.1.1 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'jsonText' Block Attribute
Affected software: wordpress-seo(Plugin)
Affected versions: ≤ 27.1.1
Authentication: Authenticated (see advisory title)
Vulnerability type: Cross-site scripting
CVE: CVE-2026-3427
Published: 21 March 2026
CISA KEV: Not listed in CISA KEV at last catalog refresh
Impact: May allow attackers to run scripts in visitors' browsers or hijack admin sessions.
Source: Data imported from Wordfence Intelligence (advisory fee1fef5-5716-49e0-a04e-d0dae527fcfc). Methodology and redistribution notes

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