# CVE-2026-5600: pretix: API leaks check-in data between events of the same organizer

> An API flaw in pretix allows unauthorized users to view check-in data for all events under an organizer, exposing ticket scan details.

- **Severity:** Medium 5.5 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:N/VA:N/SC:H/SI:H/SA:H`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 8 Apr 2026
- **Updated:** 8 Apr 2026
- **Also known as:** GHSA-wr8q-c73g-m7gp, PYSEC-2026-111

## What is CVE-2026-5600?

CVE-2026-5600 is a medium-severity missing authorization vulnerability in pretix, published on 8 Apr 2026. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

A new API endpoint introduced in pretix 2025 that is supposed to 
return all check-in events of a specific event in fact returns all 
check-in events belonging to the respective organizer. This allows an 
API consumer to access information for all other events under the same 
organizer, even those they should not have access to.

These records contain information on the time and result of every ticket scan as well as the ID of the matched ticket. Example:

{
  "id": 123,
  "successful": true,
  "error_reason": null,
  "error_explanation": null,
  "position": 321,
  "datetime": "2020-08-23T09:00:00+02:00",
  "list": 456,
  "created": "2020-08-23T09:00:00+02:00",
  "auto_checked_in": false,
  "gate": null,
  "device": 1,
  "device_id": 1,
  "type": "entry"
}

An unauthorized user usually has no way to match these IDs (position) back to individual people.

Weakness: CWE-653 (Improper Isolation or Compartmentalization)

## Which versions are affected by CVE-2026-5600?

7 open source packages ship an affected version, including pretix. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `pretix` | PyPI | From 2025.10.0 | 2026.1.2, 2026.2.1, 2026.3.1 |
| `pretix` | PyPI | From 2025.10.0 | 2026.1.2 |
| `pretix` | PyPI | From 2025.10.0 | 2026.1.2 |
| `pretix` | PyPI | From 2026.2.0 | 2026.2.1 |
| `pretix` | PyPI | From 2026.2.0 | 2026.2.1 |
| `pretix` | PyPI | From 2026.3.0 | 2026.3.1 |
| `pretix` | PyPI | From 2026.3.0 | 2026.3.1 |

Products: Pretix Pretix.

## How do I fix CVE-2026-5600?

Upgrade pretix to a fixed version for your release line: 2026.1.2, 2026.2.1 or 2026.3.1.

## Is CVE-2026-5600 being exploited?

There is no known exploitation of CVE-2026-5600 in the wild and no public exploit code.

## Other vulnerabilities in pretix

- [CVE-2024-27447](https://insights.sbomify.com/CVE-2024-27447/): pretix mishandles file validation (critical 9.8)
- [CVE-2026-2415](https://insights.sbomify.com/CVE-2026-2415/): Unsafe variable evaluation in email templates (high 7.5)
- [CVE-2024-8113](https://insights.sbomify.com/CVE-2024-8113/): Stored XSS in Placeholder Samples in Mail Preview (high 7.2)
- [CVE-2025-13742](https://insights.sbomify.com/CVE-2025-13742/): Limited HTML injection in emails (low 2.4)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-5600 and fix it if it is affected.

What it is: CVE-2026-5600 is a medium-severity missing authorization vulnerability in pretix, published on 8 Apr 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-5600 in the wild and no public exploit code.

Affected packages and fixed versions:
- pretix (PyPI): affected from 2025.10.0; fixed in 2026.1.2, 2026.2.1, 2026.3.1
- pretix (PyPI): affected from 2025.10.0; fixed in 2026.1.2
- pretix (PyPI): affected from 2025.10.0; fixed in 2026.1.2
- pretix (PyPI): affected from 2026.2.0; fixed in 2026.2.1
- pretix (PyPI): affected from 2026.2.0; fixed in 2026.2.1
- pretix (PyPI): affected from 2026.3.0; fixed in 2026.3.1
- pretix (PyPI): affected from 2026.3.0; fixed in 2026.3.1

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-2026-5600/ (Markdown: https://insights.sbomify.com/CVE-2026-5600/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-5600
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-5600
- OSV: https://osv.dev/vulnerability/CVE-2026-5600

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-5600/
Summaries are generated and may contain mistakes; the official description above is the record.