CVE-2026-41896
What it is
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=<hash_hmac('sha256', payload, '')>, an unauthenticated attacker can forge a valid signature and trigger deployments. This vulnerability is fixed in 4.0.0-beta.474.
At a glance
- Exploitability
- Can be exploited over the network without logging in. High risk of data tampering.
- Exploit odds
- 0.3% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.3% in the next 30 days (EPSS).
- Severity: 7.5 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.3% · EPSS, next 30 days
- Weakness
- CWE-287 · Improper authentication
- Record status
- Deferred
Attack profile CVSS 3.1 · 7.5
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- High
- Availability
- None
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-41896.md and follow it. Check whether this project is affected by CVE-2026-41896. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://github.com/coollabsio/coolify/security/advisories/GHSA-w8wm-r924-f65v
- https://github.com/coollabsio/coolify/security/advisories/GHSA-w8wm-r924-f65v