Horizon Alert
Summary of the vulnerability and why it matters
This advisory addresses a vulnerability in the Kimai time-tracking application, specifically within its official Docker image. The issue stems from a predictable secret key used for authentication, which, under certain conditions, could allow an unauthenticated attacker to gain unauthorized access to user accounts. The primary concern is confirming if this specific application is in use and if it has been deployed without overriding the default secret.
- Predictable key allows unauthorized account access.
- Confirm if Kimai is used; assess exposure.
- Ensure application deployments are secured.
Attack Path
How an attacker could exploit the issue
An attacker could gain unauthorized access to a Kimai account by exploiting a weakness in how the application handles secrets. If an administrator has not properly configured a unique secret for the application, an attacker who knows a username and the associated account ID, and can guess that the account lacks two-factor authentication, can forge authentication tokens. This allows them to bypass the password and take control of the account.
- Unauthenticated access to a misconfigured deployment.
- Forges authentication artifacts to impersonate a user.
- Risks unauthorized account access and data manipulation.
Live Threat
Current exploitation, exposure, and threat context
When supported by the advisory, an unauthenticated attacker could forge authentication artifacts to access user accounts without a password, provided they know a username, can guess the account ID, and the targeted account lacks two-factor authentication.
- User account access.
- Forging authentication artifacts.
- Unauthorized account access.
Operational Fix
Recommended remediation, mitigation, and detection steps
Owners of the Kimai application, likely within infrastructure or platform teams, must first confirm where Kimai is deployed and if it's internet-reachable. This is critical because the vulnerability allows unauthenticated attackers to forge authentication artifacts if the default `APP_SECRET` is not overridden and they know a username and account ID, and can guess the account ID for an account without 2FA. Vendor coordination may be necessary for patching or remediating the secret management.
- Application owners and platform teams.
- Verify `APP_SECRET` override and internet reachability.
- Plan remediation based on verified risk and exposure.
