CVE-2026-28224 Firebird Null Pointer Dereference via CryptCallback causes DOS

High 8.2 Published 17 Apr 2026 Updated 17 Apr 2026

An unauthenticated attacker can crash the Firebird database server by sending a specific packet, causing a denial of service.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2026-28224?

CVE-2026-28224 is a high-severity vulnerability in FirebirdSQL firebird, published on 17 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Firebird is an open-source relational database management system. In versions prior to 5.0.4, 4.0.7 and 3.0.14, when the server receives an op_crypt_key_callback packet without prior authentication, the port_server_crypt_callback handler is not initialized, resulting in a null pointer dereference and server crash. An unauthenticated attacker who knows only the server's IP and port can exploit this to crash the server. This issue has been fixed in versions 5.0.4, 4.0.7 and 3.0.14.

Weakness: CWE-476

Which versions are affected by CVE-2026-28224?

It affects 1 product.

Products include Firebirdsql Firebird.

How do I fix CVE-2026-28224?

Upgrade to a fixed version.

Is CVE-2026-28224 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-28224 exists.

Sources

Also known as DEBIAN-CVE-2026-28224, ECHO-370e-28b5-84b7, GHSA-xrcw-wpjx-pr95, UBUNTU-CVE-2026-28224.