# CVE-2026-94039: vas3k TaxHacker Invoice PDF Renderer actions.ts generateInvoicePDF server-side request forgery

> Remote attackers can exploit a server-side request forgery vulnerability in the Invoice PDF Renderer to access internal resources or bypass security controls.

- **Severity:** Medium 6.9 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 20 Sep 2026
- **Updated:** 21 Sep 2026
- **Also known as:** GHSA-gc9f-gc68-qrg3

## What is CVE-2026-94039?

CVE-2026-94039 is a medium-severity server-side request forgery vulnerability in vas3k TaxHacker, published on 20 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability was detected in vas3k TaxHacker up to 0.8.5. Affected is the function generateInvoicePDF of the file /apps/invoices/actions.ts of the component Invoice PDF Renderer. Performing a manipulation of the argument businessLogo results in server-side request forgery. The attack is possible to be carried out remotely. The exploit is now public and may be used. The project was informed of the problem early through an issue report but has not responded yet.

Weakness: CWE-918 (Server-Side Request Forgery)

## Which versions are affected by CVE-2026-94039?


## How do I fix CVE-2026-94039?

No fix has been published for CVE-2026-94039 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-94039 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-94039 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-94039 and fix it if it is affected.

What it is: CVE-2026-94039 is a medium-severity server-side request forgery vulnerability in vas3k TaxHacker, published on 20 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-94039 exists.

Affected product: vas3k TaxHacker. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2026-94039/ (Markdown: https://insights.sbomify.com/CVE-2026-94039/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-94039
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-94039
- OSV: https://osv.dev/vulnerability/CVE-2026-94039

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-94039/
Summaries are generated and may contain mistakes; the official description above is the record.