TI-2026-25747 Aliases CVE-2026-33337

Firebird has a buffer overflow when parsing corrupted slice packets

HIGH 72CWE-120Published 2026-04-17 · Updated 2026-04-17

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: Denial of service, Code execution
Confidentiality · integrity · availability: None · None · High
Fix status: Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-120, CWE-502 and the CVSS impact.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV

EPSS 0.00543 45th percentileScored 2026-11-07

Public exploit Yes 1 exploit referenceTagged by NVD

Fix Fixed firebird (FirebirdSQL): 3.0.14, 4.0.7, 5.0.4

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: Poc
Automatable: Yes
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
FirebirdSQL	firebird	3.0.0 to before 3.0.14; 4.0.0 to before 4.0.7; 5.0.0 to before 5.0.4	3.0.14, 4.0.7, 5.0.4	Patch available	CNA

firebird VendorFirebirdSQL Affected 3.0.0 to before 3.0.14; 4.0.0 to before 4.0.7; 5.0.0 to before 5.0.4 Fixed in 3.0.14, 4.0.7, 5.0.4 Patch available CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:firebirdsql:firebird::::::::	3.0.0 to before 3.0.14; 4.0.0 to before 4.0.7; 5.0.0 to before 5.0.4	Vulnerable	FirebirdSQL

cpe:2.3:a:firebirdsql:firebird:*:*:*:*:*:*:*:* Versions 3.0.0 to before 3.0.14; 4.0.0 to before 4.0.7; 5.0.0 to before 5.0.4 Vulnerable ·FirebirdSQL

Remediation

Fix · CNA firebird (FirebirdSQL) Fixed in 3.0.14, 4.0.7, 5.0.4

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product

Red Hat

Timeline

2026-10-02 Threatist record created from CVE-2026-33337
2026-10-25 EPSS moved to the below the 50th percentile

References

Exploit 1

https://github.com/FirebirdSQL/firebird/security/advisories/GHSA-89mq-229g-x47p

Other 3

TI-2026-22559 Firebird Null Pointer Dereference via CryptCallback causes DOS CVSS 3.1HIGH 8.2
TI-2026-22234 Firebird has Pre-Auth DOS when Processing Out of Order CNCT_specific_data Segments CVSS 3.1HIGH 8.2
TI-2026-27368 Firebird: DoS via malicious slice descriptor in slice packet CVSS 3.1HIGH 7.5
TI-2026-26527 Firebird: DoS via `op_response` packet from client CVSS 3.1HIGH 7.5
TI-2026-22547 Firebird has potential server crash via null pointer dereference when processing op_slice packet CVSS 3.1HIGH 7.5
TI-2008-00362 Integer overflow in Firebird SQL 1.0.3 and earlier, 1.5.x before 1.5.6, 2.0.x before… CVSS 2.0HIGH 7.8

See all 45 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences