CVE-2026-15421
MediumCVSS 6.4Exploitation Probability (EPSS)
Low risk23th percentile - higher than 23% of all known CVEs
Summary
The Speed Optimizer plugin for WordPress up to version 7.8.0 is vulnerable to Stored Cross-Site Scripting via Image Tag Attributes due to insufficient input sanitization and output escaping. Authenticated attackers with contributor-level access can inject arbitrary web scripts that execute when a user accesses an injected page. This is exploitable only when the Lazy Load Media option is enabled.
Risk Assessment
An attacker could inject malicious scripts that execute in other users' browsers, potentially leading to session theft, account takeover, or malware distribution.
Recommendation
Update the Speed Optimizer plugin to the latest patched version and disable the Lazy Load Media option if not essential.
Original NVD description (English source)
The Speed Optimizer – The All-In-One Performance-Boosting Plugin plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Image Tag Attributes in all versions up to, and including, 7.8.0 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. This is only exploitable when the site administrator has enabled the Lazy Load Media option in the plugin settings.