CVE-2026-54506 Vvveb: Stored XSS via sanitizeHTML() bypass in user profile bio field
Stored XSS in Vvveb CMS allows attackers to execute JavaScript via the user bio field, potentially leading to session hijacking or account takeover.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-54506?
CVE-2026-54506 is a high-severity cross-site scripting vulnerability in givanz Vvveb, published on 17 Sep 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
Vvveb is a powerful and easy to use CMS with page builder to build websites, blogs or ecommerce stores. Prior to 1.0.8.5, app/controller/user/profile.php accepts the user[bio] field and passes stored content through sanitizeHTML() in system/functions.php, whose on* event-handler regular expression omits the forward-slash delimiter and whose do-while condition compares the string to itself, so forbidden nested tags are removed only once. An Author-role or higher user can submit solidus-prefixed event-handler markup or nested forbidden tags that survive sanitization. The stored bio is rendered without sufficient output encoding on /author/{username}, in the admin user-management view, and potentially in comment displays, causing attacker-controlled JavaScript to execute when unauthenticated visitors, administrators, or other users view the content. This can expose browser-session data and permit victim-context account actions, defacement, or phishing. This issue is fixed in version 1.0.8.5.
Which versions are affected by CVE-2026-54506?
How do I fix CVE-2026-54506?
No fix has been published for CVE-2026-54506 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-2026-54506 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-54506 exists.
Sources
Also known as GHSA-5cg7-phhv-4qjr.