# CVE-2026-33934: OpenEMR's Missing Authorization in show-signature.php Allows Portal Patients to Read Staff Signatures

> Authenticated patients can read any staff member's signature image due to missing authorization checks in the signature display endpoint.

- **Severity:** Medium 4.3 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 25 Mar 2026
- **Updated:** 26 Mar 2026
- **Also known as:** GHSA-w9w5-7x6h-657q

## What is CVE-2026-33934?

CVE-2026-33934 is a medium-severity missing authorization vulnerability in Open-Emr Openemr, published on 25 Mar 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

OpenEMR is a free and open source electronic health records and medical practice management application. Versions prior to 8.0.0.3 have a missing authorization check in `portal/sign/lib/show-signature.php` that allows any authenticated patient portal user to retrieve the drawn signature image of any staff member by supplying an arbitrary `user` value in the POST body. The companion write endpoint (`save-signature.php`) was already hardened against this same issue, but the read endpoint was not updated to match. Version 8.0.0.3 patches the issue.

Weakness: CWE-862 (Missing Authorization), CWE-639 (Authorization Bypass Through User-Controlled Key)

## Which versions are affected by CVE-2026-33934?

It affects 1 product.


Products: Open-Emr Openemr.

## How do I fix CVE-2026-33934?

No fix has been published for CVE-2026-33934 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-33934 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-33934 exists.

## Other vulnerabilities in Open-Emr Openemr

- [CVE-2026-24898](https://insights.sbomify.com/CVE-2026-24898/): OpenEMR has an Unauthenticated MedEx Token Disclosure (critical 10.0)
- [CVE-2026-24849](https://insights.sbomify.com/CVE-2026-24849/): OpenEMR Arbitrary File Read Vulnerability (critical 10.0)
- [CVE-2026-24908](https://insights.sbomify.com/CVE-2026-24908/): OpenEMR has SQL Injection in Patient API Sort Parameter (critical 10.0)
- [CVE-2022-2734](https://insights.sbomify.com/CVE-2022-2734/): Improper Restriction of Rendered UI Layers or Frames in openemr/openemr (critical 10.0)
- [CVE-2024-22611](https://insights.sbomify.com/CVE-2024-22611/): SQL injection in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-33934 and fix it if it is affected.

What it is: CVE-2026-33934 is a medium-severity missing authorization vulnerability in Open-Emr Openemr, published on 25 Mar 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-33934 exists.

Affected product: Open-Emr Openemr. 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-2026-33934/ (Markdown: https://insights.sbomify.com/CVE-2026-33934/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-33934
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-33934
- OSV: https://osv.dev/vulnerability/CVE-2026-33934

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-33934/
Summaries are generated and may contain mistakes; the official description above is the record.