CVE-2026-40342CWE-22CWE-427CWE-73CWE-94

Firebird: Path Traversal + Arbitrary File Write Leads to Remote Code Execution

Critical · published April 17, 2026

CVSS v3.1
10.0
EPSS
1%
Percentile
57.6
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
10.0 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00845 · 57.6th percentile
Weaknesses
CWE-22 · Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal'); CWE-427 · Uncontrolled Search Path Element; CWE-73 · External Control of File Name or Path; CWE-94 · Improper Control of Generation of Code ('Code Injection')
Published
2026-04-17T19:22Z
EPSS history
Timeline
  • 17 APR 19:22Z
    Firebird: Path Traversal + Arbitrary File Write Leads to Remote Code Execution
    cvelistv5