CVE-2026-40342: Firebird: Path Traversal + Arbitrary File Write Leads to Remote Code Execution
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.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-40342?
CVE-2026-40342 is classified as a critical vulnerability due to its potential to allow remote code execution.
How do I fix CVE-2026-40342?
To fix CVE-2026-40342, update Firebird to versions 5.0.4 or later, 4.0.7 or later, or 3.0.14 or later.
What are the risks associated with CVE-2026-40342?
The risks associated with CVE-2026-40342 include unauthorized access and control over the database system, leading to potential data breaches.
Which versions of Firebird are affected by CVE-2026-40342?
Versions of Firebird prior to 5.0.4, 4.0.7, and 3.0.14 are affected by CVE-2026-40342.
Is there a workaround for CVE-2026-40342?
There are no known workarounds for CVE-2026-40342; the only recommended action is to upgrade to a secure version.