CVE-2026-41896: Coolify is an open-source and self-hostable tool for managing servers, applications, and databases. Prior to 4.0.0-beta.474, the HMAC key is the application's…

PriorityP346high7.5CVSS 3.1

AVNACLPRNUINSUCNIHAN

EPSS

0.23%

13.9th percentile

Coolify is an open-source and self-hostable tool for managing servers, applications, and databases. Prior to 4.0.0-beta.474, the HMAC key is the application's manual_webhook_secret_github field, which is used by Coolify's webhook endpoints to validate incoming requests, is nullable with no default — meaning newly created applications have a null webhook secret. PHP's hash_hmac() function silently coerces a null key to an empty string ''. So when the secret is null, the server computes hash_hmac('sha256', $payload, '') — a deterministic value that any attacker can calculate independently. By sending X-Hub-Signature-256: sha256=, an unauthenticated attacker can forge a valid signature and trigger deployments. This vulnerability is fixed in 4.0.0-beta.474.

Affected

1 ranges

Vendor	Product	Version range	Fixed in
coollabsio	coolify	< 4.0.0-beta.474	4.0.0-beta.474

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