Kimai has Missing Voter Check that Allows Cross-Team Timesheet Manipulation

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

5.7 · CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P · score source

EPSS

No dated EPSS signal available.

As published by the source; long descriptions are shortened.

Summary Any ROLETEAMLEAD user can enumerate, read, modify, and permanently delete timesheets belonging to any other user in the system — regardless of team membership. This enables data destruction (deleted billable hours), data tampering (forged timesheet durations), and full authorization bypass on timesheet resources. Verified against Kimai 2.52.0. Details TimesheetVoter::voteOnAttribute() maps permissions to owntimesheet or othertimesheet without checking team membership. The voter's own comment confirms this is a known gap: PoC Tested against Kimai 2.52.0 Docker instance. Setup: - User A (usera, ROLETEAMLEAD) owns timesheet ID 2 with description "Private timesheet - UserA only" - User B (userb, ROLETEAMLEAD) is NOT on any team with User A User B reads User A's timesheet data: Response: HTTP 200 — returns full timesheet record including description "Private timesheet - UserA only". User B deletes User A's timesheet: Response: HTTP 204 No Content — timesheet permanently deleted.…

Published by the source

6 May 2026, 18:28 UTC

Last modified by the source

6 May 2026, 18:28 UTC

Source last checked

26 Oct 2026, 14:39 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-9g2q-w3w2-vf7q

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: GHSA-9g2q-w3w2-vf7q

Advisory: Kimai has Missing Voter Check that Allows Cross-Team Timesheet Manipulation
IDs: GHSA-9g2q-w3w2-vf7q
Record: https://patchnext.com/advisories/ghsa-9g2q-w3w2-vf7q (revision 1, source checked 26 Oct 2026, 14:39 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.7)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: kimai/kimai 2.56.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Packagist kimai/kimai: affected <= 2.55.0; fixed in 2.56.0

## Suggested inspection (read-only)
- Packagist kimai/kimai: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on kimai/kimai.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-9g2q-w3w2-vf7q (GitHub-reviewed advisory GHSA-9g2q-w3w2-vf7q lists affected ranges: Packagist kimai/kimai >=0 <=2.55.0)

Commands are suggestions: review each one before running it.