CVE-2026-44401 Typemill CMS 2.x Persistent XSS via Markdown javascript URI
Authenticated attackers can inject malicious JavaScript via Markdown links in Typemill CMS, leading to session theft and credential harvesting for site visitors.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-44401?
CVE-2026-44401 is a medium-severity cross-site scripting vulnerability in Typemill, published on 10 Aug 2026. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.
Official description
Typemill CMS version 2.x contains a persistent cross-site scripting vulnerability in the Markdown parser extension that allows authenticated users with theme-configuration access to inject malicious JavaScript URIs by supplying unsanitized href values in Markdown links. Attackers can craft Markdown links using the javascript: scheme through ParsedownExtension.php or TwigMarkdownExtension.php, storing a persistent payload that executes in the browser of every visitor who clicks the link, enabling session cookie theft, authenticated request forgery, and credential harvesting.
Weakness: CWE-79
Which versions are affected by CVE-2026-44401?
How do I fix CVE-2026-44401?
No fix has been published for CVE-2026-44401 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-2026-44401 being exploited?
There is no known exploitation of CVE-2026-44401 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Sources
Also known as GHSA-8vfw-vh7q-p649.