CVE-2026-52823
CVE-2026-52823 is a security vulnerability in kimai/kimai. O3 Security confirms whether CVE-2026-52823 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Kimai: Login CSRF in the Timesheet Stop and Restart API Endpoints Allows Unauthorized State Changes
Real-World Exposure
kimai/kimaiReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
Summary
Kimai 2.56.0 contains authenticated cross-site request forgery issues in its timesheet state-changing API endpoints. The application reuses the browser's existing session for /api/* requests, and both the stop and restart operations are exposed through GET and PATCH routes that directly modify business state.
As a result, an attacker can trick a logged-in user into visiting a malicious page and cause unauthorized timesheet actions without the victim's consent. Depending on the endpoint, this can stop a running timesheet or create and start a new one from historical data.
Details
The issue affects at least the following API routes:
GET /api/timesheets/{id}/stopGET /api/timesheets/{id}/restart
Both routes are non-read-only operations but are still exposed as GET. In src/API/TimesheetController.php.
A PoC was provided, but removed for security reasons.
Impact
This vulnerability allows an attacker to trigger unauthorized business-state changes as a logged-in victim. In the validated stop case, a running timesheet can be stopped, affecting time tracking integrity and potentially availability of ongoing work tracking. In the restart case, a historical timesheet can be restarted and a new record can be created without the victim's knowledge.
These actions can corrupt time records, distort billing and reporting, interfere with approvals or audits, and create persistent database-side side effects. Because exploitation requires only that the victim visit a malicious page while authenticated, the attack barrier is low.
Solution
The GET routes were removed, both stop and restart are only available via PATCH.
See https://www.kimai.org/en/security/ghsa-r8vr-m544-qh4h for more information.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | kimai/kimai | all versions | 2.58.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for kimai/kimai. 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 kimai/kimai to 2.58.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-52823 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-2026-52823 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-2026-52823. 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-2026-52823 in your dependencies?
O3 detects CVE-2026-52823 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.