CVE-2026-33337

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.

Weakness classification

• CWE-120: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
• CWE-502: Deserialization of Untrusted Data

Primary references

• security-advisories@github.com — Release Notes
• security-advisories@github.com — Release Notes
• security-advisories@github.com — Release Notes
• security-advisories@github.com — Exploit, Vendor Advisory