CVE-2026-33628: Invoice Ninja Denylist Bypass may Lead to Stored XSS via Invoice Line Items
Vulnerability Details
Invoice line item descriptions in Invoice Ninja v5.13.0 bypass the XSS denylist filter, allowing stored XSS payloads to execute when invoices are rendered in the PDF preview or client portal.
The line item description field was not passed through purify::clean() before rendering.
Steps to Reproduce
1. Login as any authenticated user 2. Create or edit an invoice 3. In a line item description, enter: <img src=x onerror=alert(document.cookie)> 4. Save the invoice and preview it 5. The XSS payload executes in the browser
Impact
- Attacker: Any authenticated user who can create invoices - Victim: Any user viewing the invoice (including clients via the portal) - Specific damage: Session hijacking, account takeover, data exfiltration
Proposed Fix
Fixed in v5.13.4 by the vendor by adding purify::clean() to sanitize line item descriptions.
Other sources
Invoice Ninja is a source-available invoice, quote, project and time-tracking app built with Laravel. Invoice line item descriptions in Invoice Ninja v5.13.0 bypass the XSS denylist filter, allowing stored XSS payloads to execute when invoices are rendered in the PDF preview or client portal. The line item description field was not passed through purify::clean() before rendering. This is fixed in v5.13.4 by the vendor by adding purify::clean() to sanitize line item descriptions.
— MITRE
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2026-33628?
CVE-2026-33628 has a high severity due to its ability to execute stored XSS payloads.
How do I fix CVE-2026-33628?
To fix CVE-2026-33628, update Invoice Ninja to version 5.13.4 or later.
What software is affected by CVE-2026-33628?
CVE-2026-33628 affects Invoice Ninja versions prior to 5.13.4.
What causes the CVE-2026-33628 vulnerability?
CVE-2026-33628 is caused by the invoice line item description field bypassing the XSS denylist filter.
In what scenarios can CVE-2026-33628 be exploited?
CVE-2026-33628 can be exploited when invoices are rendered in the PDF preview or client portal.