CVE-2026-5032 W3 Total Cache <= 2.9.3 - Unauthenticated Security Token Exposure via User-Agent Header
Unauthenticated attackers can leak security tokens via User-Agent headers, enabling remote code execution if fragment caching is enabled.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-5032?
CVE-2026-5032 is a high-severity vulnerability in boldgrid W3 Total Cache, published on 2 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
The W3 Total Cache plugin for WordPress is vulnerable to information exposure in all versions up to, and including, 2.9.3. This is due to the plugin bypassing its entire output buffering and processing pipeline when the request's User-Agent header contains "W3 Total Cache", which causes raw mfunc/mclude dynamic fragment HTML comments — including the W3TC_DYNAMIC_SECURITY security token — to be rendered in the page source. This makes it possible for unauthenticated attackers to discover the value of the W3TC_DYNAMIC_SECURITY constant by sending a crafted User-Agent header to any page that contains developer-placed dynamic fragment tags, granted the site has the fragment caching feature enabled. With the leaked W3TC_DYNAMIC_SECURITY token, an attacker can craft valid mfunc tags to execute arbitrary PHP code on the server, achieving remote code execution.
Weakness: CWE-200
Which versions are affected by CVE-2026-5032?
How do I fix CVE-2026-5032?
No fix has been published for CVE-2026-5032 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-5032 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-5032 exists.
Public exploit code: 1 Nuclei template.
Sources
Also known as GHSA-fxg7-rh9m-q77p.