CVE-2026-40342 CRITICAL

CVE-2026-40342: Firebird: Path Traversal + Arbitrary File Write Leads to Remote Code Execution

Vendor Firebirdsql
Product firebird
Weakness CWE-22 · Path traversal
Published April 17, 2026
Last update April 22, 2026

CVSS base score

10.0/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality High
Integrity High

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

What the vulnerability does

01Description

Firebird is an open-source relational database management system. In versions prior to 5.0.4, 4.0.7 and 3.0.14, the external engine plugin loader concatenates a user-supplied engine name into a filesystem path without filtering path separators or .. components. An authenticated user with CREATE FUNCTION privileges can use a crafted ENGINE name to load an arbitrary shared library from anywhere on the filesystem via path traversal. The library's initialization code executes immediately during loading, before Firebird validates the module, achieving code execution as the server's OS account. This issue has been fixed in versions 5.0.4, 4.0.7 and 3.0.14.

Key dates

02Disclosure timeline

April 17, 2026 CVE published
April 22, 2026 Record updated