# CVE-2026-33628: Invoice Ninja Denylist Bypass may Lead to Stored XSS via Invoice Line Items

> Attackers can inject stored XSS payloads into invoice line items, potentially compromising user sessions in the client portal or PDF previews.

- **Severity:** Medium 5.4 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N`)
- **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 available:** Yes
- **Published:** 26 Mar 2026
- **Updated:** 27 Mar 2026
- **Also known as:** GHSA-98wm-cxpw-847p

## What is CVE-2026-33628?

CVE-2026-33628 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. 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.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation), CWE-184 (Incomplete List of Disallowed Inputs), CWE-116 (Improper Encoding or Escaping of Output)

## Which versions are affected by CVE-2026-33628?

2 open source packages ship an affected version, including invoiceninja/invoiceninja. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `invoiceninja/invoiceninja` | Packagist | All versions | 5.13.4 |
| `invoiceninja/invoiceninja` | Packagist | All versions | 5.13.4 |

Products: Invoiceninja Invoice Ninja.

## How do I fix CVE-2026-33628?

Upgrade invoiceninja/invoiceninja to 5.13.4 or later.

## Is CVE-2026-33628 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-33628 exists.

## Other vulnerabilities in invoiceninja

- [CVE-2021-33898](https://insights.sbomify.com/CVE-2021-33898/): Deserialization in n/a (high 8.1)
- [CVE-2026-29925](https://insights.sbomify.com/CVE-2026-29925/): Server-side request forgery in n/a (high 7.7)
- [CVE-2021-3977](https://insights.sbomify.com/CVE-2021-3977/): Cross-site Scripting (XSS) - Stored in invoiceninja/invoiceninja (medium 6.5)
- [CVE-2026-33742](https://insights.sbomify.com/CVE-2026-33742/): Invoice Ninja has Stored XSS via Markdown HTML Injection in Product Notes (medium 5.4)
- [CVE-2017-1000466](https://insights.sbomify.com/CVE-2017-1000466/): Cross-site scripting in n/a (medium 5.4)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-33628 and fix it if it is affected.

What it is: CVE-2026-33628 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.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-33628 exists.

Affected packages and fixed versions:
- invoiceninja/invoiceninja (Packagist): affected all versions; fixed in 5.13.4
- invoiceninja/invoiceninja (Packagist): affected all versions; fixed in 5.13.4

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-33628/ (Markdown: https://insights.sbomify.com/CVE-2026-33628/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-33628
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-33628
- OSV: https://osv.dev/vulnerability/CVE-2026-33628

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-33628/
Summaries are generated and may contain mistakes; the official description above is the record.