CVE-2026-52820
CVE-2026-52820 — Kimai: Timesheet PATCH/POST allows assigning to project outside user's team via query_builder OR-bypass
Kimai is an open-source time tracking application. Prior to 2.57.0, PATCH /api/timesheets/{id} and POST /api/timesheets accept a user-controlled project identifier through TimesheetApiEditForm and FormTrait, and ProjectRepository::getQueryBuilderForFormType() places that identifier in an unconditional OR branch that bypasses the team access criteria. Any authenticated user with edit_own_timesheet can therefore assign an owned timesheet to a project outside the user's teams, persist unauthorized project attribution, and retrieve project and customer metadata through GET /api/timesheets/{id}?full=true. TimesheetTeamAccessValidator now checks changed project and activity associations against current team access. This issue is fixed in version 2.57.0.
Published Updated Sources: cvelistV5, GitHub_M
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.
Exploitation
Unreported
no source claims exploitation
EPSS
0%
chance of exploitation in 30 days
CVSS base
5.3
MEDIUM
CISA SSVC assessment
Three decision points CISA publishes for the CVEs it assesses · SSVC 2.0.3. A stakeholder decision, not a severity score.
Exploitation
None
none · proof-of-concept · active
Automatable
No
can an attacker script all four kill-chain steps
Technical impact
Partial
partial · total control of the vulnerable component
Affected scope
The catalog records vendors and products as separate lists, not pairs, so which product belongs to which vendor is not something this page can say.
Vendors (1)
Products (1)
Every base score collected
Sources score independently and disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Source |
|---|---|---|---|---|---|
| 5.3 | CVSS 4.0 | MEDIUM | — | — | cvelistV5 |
Weakness & attack patterns
- CWE-639
Detection
Read off the CVSS vector and the weakness class. Starting points, not rules we have tested.
- Search application, proxy, and WAF logs for requests touching /api/timesheets/, /api/timesheets.
References
5 on the record
- github.com/kimai/kimai/security/advisories/GHSA-vrr2-g9gh-c3jc
x_refsource_CONFIRM
- github.com/kimai/kimai/pull/5929
x_refsource_MISC
- github.com/kimai/kimai/commit/976d38e8a4485a1c923ee7b5841849e91a06e849
x_refsource_MISC
- github.com/kimai/kimai/releases/tag/2.57.0
x_refsource_MISC
- www.kimai.org/en/security/ghsa-vrr2-g9gh-c3jc
x_refsource_MISC
Elsewhere on this site
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.