# CVE-2026-40486: Kimai's User Preferences API allows standard users to modify restricted attributes: hourly_rate, internal_rate

> Authenticated users can bypass permission checks to modify restricted billing rates, leading to unauthorized financial data tampering.

- **Severity:** Medium 4.3 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 17 Apr 2026
- **Updated:** 20 Apr 2026
- **Also known as:** GHSA-qh43-xrjm-4ggp

## What is CVE-2026-40486?

CVE-2026-40486 is a medium-severity missing authorization vulnerability in kimai, published on 17 Apr 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Kimai is an open-source time tracking application. In versions 2.52.0 and below, the User Preferences API endpoint (PATCH /api/users/{id}/preferences) applies submitted preference values without checking the isEnabled() flag on preference objects. Although the hourly_rate and internal_rate fields are correctly marked as disabled for users lacking the hourly-rate role permission, the API ignores this restriction and saves the values directly. Any authenticated user can modify their own billing rates through this endpoint, resulting in unauthorized financial tampering affecting invoices and timesheet calculations. This issue has been fixed in version 2.53.0.

Weakness: CWE-915 (Improperly Controlled Modification of Dynamically-Determined Object Attributes)

## Which versions are affected by CVE-2026-40486?

2 open source packages ship an affected version, including kimai/kimai. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `kimai/kimai` | Packagist | All versions | 2.53.0 |
| `kimai/kimai` | Packagist | All versions | 2.53.0 |

Products: Kimai Kimai.

## How do I fix CVE-2026-40486?

Upgrade kimai/kimai to 2.53.0 or later.

## Is CVE-2026-40486 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-40486 exists.

## Other vulnerabilities in kimai

- [CVE-2020-19825](https://insights.sbomify.com/CVE-2020-19825/): Cross-site Scripting in kimai/kimai (critical 9.6)
- [CVE-2023-53957](https://insights.sbomify.com/CVE-2023-53957/): Kimai 1.30.10 SameSite Cookie Vulnerability Session Hijacking (high 8.5)
- [CVE-2021-43515](https://insights.sbomify.com/CVE-2021-43515/): Improper Neutralization of Formula Elements in a CSV File in Kimai 2 (high 7.8)
- [CVE-2023-46245](https://insights.sbomify.com/CVE-2023-46245/): Kimai (Authenticated) SSTI to RCE by Uploading a Malicious Twig File (high 7.2)
- [CVE-2026-23626](https://insights.sbomify.com/CVE-2026-23626/): Kimai Vulnerable to Authenticated Server-Side Template Injection (SSTI) (medium 6.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-40486 and fix it if it is affected.

What it is: CVE-2026-40486 is a medium-severity missing authorization vulnerability in kimai, published on 17 Apr 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-40486 exists.

Affected packages and fixed versions:
- kimai/kimai (Packagist): affected all versions; fixed in 2.53.0
- kimai/kimai (Packagist): affected all versions; fixed in 2.53.0

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-40486/ (Markdown: https://insights.sbomify.com/CVE-2026-40486/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-40486
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-40486
- OSV: https://osv.dev/vulnerability/CVE-2026-40486

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-40486/
Summaries are generated and may contain mistakes; the official description above is the record.