CVE-2026-27890

Severity CVSS v4.0:

Pending analysis

Type:

CWE-119 Buffer Errors

Publication date:

17/04/2026

Last modified:

20/04/2026

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 processing CNCT_specific_data segments during authentication, the server assumes segments arrive in strictly ascending order. If segments arrive out of order, the Array class&#39;s grow() method computes a negative size value, causing a SIGSEGV crash. An unauthenticated attacker who knows only the server&#39;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.

Impact

Vector 3.x

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H CVSS v3.1 Severity and Metrics:

Base Score: 8.20 HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): None
Integrity (I): Low
Availability (A): High

Base Score 3.x

8.20

Severity 3.x

HIGH

CVE-2026-27890

Description

Impact

References to Advisories, Solutions, and Tools