CVE-2026-78077 Cross-site scripting in Helix Ultimate extension for Joomla
Attackers can inject malicious scripts via unsanitized MegaMenu configuration values, leading to stored XSS in the Helix Ultimate Joomla extension.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-78077?
CVE-2026-78077 is a high-severity cross-site scripting vulnerability in joomshaper.com Helix Ultimate extension for Joomla, published on 31 Aug 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Official description
Joomla Extension - joomshaper.com - Stored Cross-Site Scripting (XSS) in MegaMenu Layout Container & Embed Inputs in Helix Ultimate < 2.2.10 - Unsanitized column and item configuration values stored within the MegaMenu layout JSON were rendered without complete contextual escaping, allowing injection of malicious HTML/JS. Stricter sanitization and tag allowlists via `InputFilter` and `htmlspecialchars` were implemented.
Weakness: CWE-79
Which versions are affected by CVE-2026-78077?
How do I fix CVE-2026-78077?
No fix has been published for CVE-2026-78077 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-2026-78077 being exploited?
There is no known exploitation of CVE-2026-78077 in the wild and no public exploit code.
Sources
Also known as GHSA-v6p2-jx9w-8967.