CVE-2026-33337: Firebird is an open-source relational database management system. In versions prior to 5.0.4, 4.0.7 and 3.0.14, when…
CVE-2026-33337 · Severity: high · CVSS 7.5 · Published 2026-04-17
Firebird is an open-source relational database management system. In versions prior to 5.0.4, 4.0.7 and 3.0.14, when deserializing a slice packet, the xdr_datum() function does not validate that a cstring length conforms to the slice descriptor bounds, allowing a cstring longer than the allocated buffer to overflow it. An unauthenticated attacker can exploit this by sending a crafted packet to the server, potentially causing a crash or other security impact. This issue has been fixed in versions 5.0.4, 4.0.7 and 3.0.14.
No. Junglewise Threat Intelligence has no report of CVE-2026-33337 being exploited in the wild.
How severe is CVE-2026-33337?
High severity, with a CVSS score of 7.5, published 17 April 2026.
Which products and versions are affected?
Firebirdsql Firebird. The advisory does not name versions.
Is there a fix for CVE-2026-33337?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
Am I affected by CVE-2026-33337?
Check whether you run Firebirdsql Firebird. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.