CVE-2026-5600
CVE-2026-5600 is a CWE-653 vulnerability in pretix. O3 Security confirms whether CVE-2026-5600 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
pretix: API leaks check-in data between events of the same organizer
Blast Radius
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 | 2026.3.1 |
| 🐍PyPI | pretix | ≥ 2026.2.0&&< 2026.2.1 | 2026.2.1 |
| 🐍PyPI | pretix | ≥ 2025.10.0&&< 2026.1.2 | 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. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
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 pinpoints whether CVE-2026-5600 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
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 detects CVE-2026-5600 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.