CVE-2026-71249 299Ko - Unauthenticated Reflected XSS in Public Contact Form
Unauthenticated attackers can inject malicious scripts via the public contact form, potentially leading to session hijacking or code execution.
- 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-2026-71249?
CVE-2026-71249 is a medium-severity cross-site scripting vulnerability in 299Ko, published on 5 Aug 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
299Ko's public contact form (plugin/contact/controllers/ContactController.php, home) sets raw POST field values (name, firstname, email, message) into the page template with no sanitization. The template engine's variable output function (common/Template.php, _show_var) echoes values with no htmlspecialchars call, and the sink template (contact.tpl) outputs these values unescaped into an HTML attribute and a textarea.
Weakness: CWE-79
Which versions are affected by CVE-2026-71249?
How do I fix CVE-2026-71249?
No fix has been published for CVE-2026-71249 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-2026-71249 being exploited?
There is no known exploitation of CVE-2026-71249 in the wild and no public exploit code.
Sources
Also known as GHSA-pf9g-3vw7-vgqf.