CVE-2026-3220 Multiple Plugins - Unauthenticated Stored XSS via Minify Library
Unauthenticated attackers can inject arbitrary HTML attributes via predictable minification hashes, leading to stored XSS in affected WordPress caching plugins.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-3220?
CVE-2026-3220 is a high-severity cross-site scripting vulnerability in Unknown Autoptimize, published on 18 May 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official 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.
Weakness: CWE-79
Which versions are affected by CVE-2026-3220?
How do I fix CVE-2026-3220?
No fix has been published for CVE-2026-3220 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-3220 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-3220 exists.
Sources
Also known as GHSA-3jpv-pgxw-p274.