CVE-2026-5600 — pretix
CVE-2026-5600 is a CWE-653 vulnerability in pretix. A fix is available for pretix — see the affected versions and patch details below.
pretix: API leaks check-in data between events of the same organizer
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-5600.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Real-World Exposure
pretix🐍pretix🐍pretixReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | pretix | ≥ 2026.3.0&&< 2026.3.1 | 2026.3.1pip install --upgrade 'pretix==2026.3.1' |
| 🐍PyPI | pretix | ≥ 2026.2.0&&< 2026.2.1 | 2026.2.1pip install --upgrade 'pretix==2026.2.1' |
| 🐍PyPI | pretix | ≥ 2025.10.0&&< 2026.1.2 | 2026.1.2pip install --upgrade 'pretix==2026.1.2' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pretix, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update pretix to 2026.3.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-5600 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-5600 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-5600. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-5600 in your dependencies?
O3 Security finds CVE-2026-5600 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.