CVE-2026-8900
MediumCVSS 6.4Exploitation Probability (EPSS)
Low risk9th percentile - higher than 9% of all known CVEs
Summary
The Simple SEO Slideshow plugin for WordPress up to version 1.2.8 has a stored XSS vulnerability via shortcode attributes. Authenticated attackers with contributor-level access can inject arbitrary scripts that execute on every page visit. WordPress KSES does not strip malicious shortcode attribute values on post save.
Risk Assessment
The risk involves script execution in all visitors' browsers, including administrators, potentially leading to data theft or session hijacking.
Recommendation
Update the Simple SEO Slideshow plugin to the latest version. If unavailable, temporarily disable the plugin and apply WAF rules to block malicious shortcode attributes.
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Original NVD description (English source)
The Simple SEO Slideshow plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Shortcode Attributes in all versions up to, and including, 1.2.8 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. WordPress KSES does not strip malicious shortcode attribute values on post save, allowing contributor-level users to persist payloads that execute for any visitor, including administrators reviewing the post.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

