CVE-2026-33337

Name: CVE-2026-33337
Creator: NVD / NIST
Published: 2026-04-17T19:16:36.223+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 0.54%

Last modified Jun 17, 2026

CVE-2026-33337 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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. EPSS estimates a 0.54% chance of exploitation in the next 30 days.

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 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.

Metrics

CVSS 3.1

7.5/10

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

EPSS Probability

0.54%

41.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Firebirdsql	Firebird	>= 3.0.0, < 3.0.14
Firebirdsql	Firebird	>= 4.0.0, < 4.0.7
Firebirdsql	Firebird	>= 5.0.0, < 5.0.4

References

https://github.com/FirebirdSQL/firebird/releases/tag/v3.0.14Release Notes
https://github.com/FirebirdSQL/firebird/releases/tag/v4.0.7Release Notes
https://github.com/FirebirdSQL/firebird/releases/tag/v5.0.4Release Notes
https://github.com/FirebirdSQL/firebird/security/advisories/GHSA-89mq-229g-x47pExploit, Vendor Advisory

Timeline

Published: Apr 17, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-33337?

How severe is CVE-2026-33337?

CVE-2026-33337 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 0.54% probability of exploitation in the next 30 days.

How do I fix CVE-2026-33337?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-33337?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST