CVE-2026-33742 Invoice Ninja has Stored XSS via Markdown HTML Injection in Product Notes
Attackers can inject malicious scripts via product notes, leading to stored XSS and potential account takeover in Invoice Ninja.
- 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-2026-33742?
CVE-2026-33742 is a medium-severity cross-site scripting vulnerability in invoiceninja, published on 26 Mar 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
Invoice Ninja is a source-available invoice, quote, project and time-tracking app built with Laravel. Product notes fields in Invoice Ninja v5.13.0 allow raw HTML via Markdown rendering, enabling stored XSS. The Markdown parser output was not sanitized with `purify::clean()` before being included in invoice templates. This is fixed in v5.13.4 by the vendor by adding `purify::clean()` to sanitize Markdown output.
Weakness: CWE-79
Which versions are affected by CVE-2026-33742?
It affects 1 product.
Products include Invoiceninja Invoice Ninja.
How do I fix CVE-2026-33742?
No fix has been published for CVE-2026-33742 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-2026-33742 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-33742 exists.
Other vulnerabilities in invoiceninja
- CVE-2021-33898 Deserialization in n/a
- CVE-2026-29925 Server-side request forgery in n/a
- CVE-2021-3977 Cross-site Scripting (XSS) - Stored in invoiceninja/invoiceninja
- CVE-2026-33628 Invoice Ninja Denylist Bypass may Lead to Stored XSS via Invoice Line Items
- CVE-2017-1000466 Cross-site scripting in n/a
Sources
Also known as GHSA-xph7-9749-56mh.