Medium severity · published Mar 26, 2026
CVE-2026-33742
Invoice Ninja has Stored XSS via Markdown HTML Injection in Product Notes
5.4
CVSS
0.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 11% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
IN
invoiceninja · invoiceninja
< 5.13.4 · source: vendor
IN
Invoice Ninja · Invoiceninja
before 5.13.4 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-33742
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-33742
Release Notes
https://github.com/invoiceninja/invoiceninja/releases/tag/v5.13.4
Exploit
https://github.com/invoiceninja/invoiceninja/security/advisories/GHSA-xph7-9749-56mh
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