CVE-2026-3220
High
Description
The Autoptimize WordPress plugin before 3.1.15, Clearfy Cache WordPress plugin before 2.4.2, Speed Optimizer WordPress plugin before 7.7.9 are vulnerable to unauthenticated Stored Cross-Site Scripting (XSS) due to a predictable replacement hash used during the HTML minification process and abusing a regular expression. This allows an attacker to inject arbitrary HTML attributes in the final HTML output by anticipating the placeholder format.
SeverityHigh
CVSS8.8
Exploit probability—
Product
Autoptimize
PublishedMay 18, 2026
First seenMay 18, 2026
Weakness typeCWE-79Cross-site scripting (XSS)
How to fix
Update
- Autoptimize3.1.15 or later
- Clearfy Cache2.4.2 or later
- Speed Optimizer7.7.9 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| Autoptimize | v < 3.1.15 | 3.1.15 |
| Clearfy Cache | v < 2.4.2 | 2.4.2 |
| Speed Optimizer | v < 7.7.9 | 7.7.9 |
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