CVE-2026-52823: Kimai Login CSRF Vulnerability

MODERATE
Advisory Identifier: GHSA-r8vr-m544-qh4h
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CWE-352
Published
Advisory Summary

CVE-2026-52823 is a MODERATE login csrf vulnerability (CWE-352: Cross-Site Request Forgery (CSRF)) affecting Kimai libraries in the Packagist ecosystem. The issue involves login csrf in the timesheet stop and restart api endpoints allows unauthorized state changes. Remediation is available by upgrading affected packages to version 2.58.0.

CVE-2026-52823 at a Glance

CVE Identifier CVE-2026-52823
GHSA Identifier GHSA-r8vr-m544-qh4h
Severity MODERATE
CVSS v3.1 Base Score N/A
CWE Classification CWE-352: Cross-Site Request Forgery (CSRF)
Affected Product Kimai
Package Ecosystem Packagist
Published Date
Last Updated

How to Fix CVE-2026-52823

To remediate this vulnerability, upgrade all affected Kimai dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

kimai/kimai fixed: 2.58.0 
Upgrade kimai/kimai to 2.58.0
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for kimai/kimai

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-52823, inspect your project dependencies for Kimai:

inspect dependencies for kimai/kimai

Analyze the terminal output to locate any version of Kimai in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.58.0), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-352: Cross-Site Request Forgery (CSRF), where the web application does not, or cannot, sufficiently verify whether a request was intentionally provided by the user who sent the request, which could have originated from an unauthorized actor. In Kimai, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### 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}/stop` - `GET /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](https://www.kimai.org/en/security/ghsa-r8vr-m544-qh4h) for more information.

CVE-2026-52823 Affected Kimai Versions

1 component(s)
Fixed Versions:
2.58.0
Product / Package Ecosystem Affected Versions Fixed Version
kimai/kimai
 Packagist
< 2.58.0
2.58.0

References

GitHub Advisory / Wiki ADVISORY
https://github.com/kimai/kimai/security/advisories/GHSA-r8vr-m544-qh4h
Kimai Source Repository REPOSITORY
https://github.com/kimai/kimai

Frequently Asked Questions

What is CVE-2026-52823?
CVE-2026-52823 is a security vulnerability in Kimai involving Login CSRF in the Timesheet Stop and Restart API Endpoints Allows Unauthorized State Changes under CWE-352: Cross-Site Request Forgery (CSRF).
Which Kimai versions are affected?
Affected versions include releases prior to 2.58.0 across affected packages: kimai/kimai.
What version fixes CVE-2026-52823?
Upgrading to 2.58.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is kimai/kimai affected?
Yes, kimai/kimai is affected in releases prior to 2.58.0. Upgrade your dependency to 2.58.0 or later.
What CWE is associated with CVE-2026-52823?
CVE-2026-52823 is classified under CWE-352: Cross-Site Request Forgery (CSRF) (The web application does not, or cannot, sufficiently verify whether a request was intentionally provided by the user who sent the request, which could have originated from an unauthorized actor.).
How can I check Packagist dependencies for CVE-2026-52823?
Run the dependency tree command: 'inspect dependencies for kimai/kimai'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-r8vr-m544-qh4h",
  "modified" : "2026-07-14T00:05:04Z",
  "published" : "2026-07-14T00:05:04Z",
  "aliases" : [ "CVE-2026-52823" ],
  "summary" : "Kimai: Login CSRF in the Timesheet Stop and Restart API Endpoints Allows Unauthorized State Changes",
  "details" : "### Summary\n\nKimai 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.\n\nAs 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.\n\n### Details\n\nThe issue affects at least the following API routes:\n\n- `GET /api/timesheets/{id}/stop`\n- `GET /api/timesheets/{id}/restart`\n\nBoth routes are non-read-only operations but are still exposed as `GET`. In `src/API/TimesheetController.php`.\n\n*A PoC was provided, but removed for security reasons.*\n\n### Impact\n\nThis 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.\n\nThese 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.\n\n# Solution\n\nThe `GET` routes were removed, both `stop` and `restart` are only available via `PATCH`.\n\nSee [https://www.kimai.org/en/security/ghsa-r8vr-m544-qh4h](https://www.kimai.org/en/security/ghsa-r8vr-m544-qh4h) for more information.",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "kimai/kimai"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2.58.0"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 2.57.0"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/kimai/kimai/security/advisories/GHSA-r8vr-m544-qh4h"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/kimai/kimai"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-352" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-07-14T00:05:04Z",
    "nvd_published_at" : null
  }
}