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 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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/FirebirdSQL/firebird/releases/tag/v3.0.14	Release Notes
https://github.com/FirebirdSQL/firebird/releases/tag/v4.0.7	Release Notes
https://github.com/FirebirdSQL/firebird/releases/tag/v5.0.4	Release Notes
https://github.com/FirebirdSQL/firebird/security/advisories/GHSA-89mq-229g-x47p	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:firebirdsql:firebird::::::::
	cpe:2.3:a:firebirdsql:firebird::::::::
	cpe:2.3:a:firebirdsql:firebird::::::::

History

No history.

Information

Published : 2026-04-17 19:16

Updated : 2026-06-17 10:37

NVD link : CVE-2026-33337

Mitre link : CVE-2026-33337

CVE.ORG link : CVE-2026-33337

JSON object : View

Products Affected

firebirdsql

firebird

CWE

CWE-120

Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

CWE-502

Deserialization of Untrusted Data

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