CVE-2026-3876 Prismatic <= 3.7.3 - Unauthenticated Stored Cross-Site Scripting via 'prismatic_encoded' Pseudo-Shortcode
Unauthenticated attackers can inject arbitrary web scripts via comments, leading to code execution when users view the page.
- 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-2026-3876?
CVE-2026-3876 is a high-severity cross-site scripting vulnerability in specialk Prismatic, published on 16 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
The Prismatic plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'prismatic_encoded' pseudo-shortcode in all versions up to, and including, 3.7.3. This is due to insufficient input sanitization and output escaping on user-supplied attributes within the 'prismatic_decode' function. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page by submitting a comment containing a crafted 'prismatic_encoded' pseudo-shortcode.
Weakness: CWE-79
Which versions are affected by CVE-2026-3876?
How do I fix CVE-2026-3876?
No fix has been published for CVE-2026-3876 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-2026-3876 being exploited?
There is no known exploitation of CVE-2026-3876 in the wild and no public exploit code.
Sources
Also known as GHSA-4mcf-jj9c-gvp6.