NULL pointer dereference in Firebird - CVE-2026-28212

Vulnerability identifier: #VU126557

CSH Severity: Medium

CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-28212

CWE-ID: CWE-476

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to a null pointer dereference in xdr_slice() when processing an op_slice packet. A remote attacker can send a specially crafted packet to cause a denial of service.

The issue is triggered when slice_response->p_slr_sdl is unprepared and contains a null pointer that is passed to SDL_info(), causing the server to crash with SIGSEGV.

Firebird
SUSE Linux Enterprise Desktop 15
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Package Hub 15
firebird
firebird-debugsource
libib_util
firebird-examples
libfbclient2
libib_util-debuginfo
firebird-utils
firebird-server
libib_util-devel
libfbclient2-debuginfo
firebird-server-debuginfo
firebird-utils-debuginfo
libfbclient-devel
firebird-debuginfo

Install security update from vendor's website.

Firebird - addressed in versions 3.0.14, 4.0.7, 5.0.4
firebird - update to 3.0.14.33856-150200.3.9.1
firebird-debugsource - update to 3.0.14.33856-150200.3.9.1
libib_util - update to 3.0.14.33856-150200.3.9.1
firebird-examples - update to 3.0.14.33856-150200.3.9.1
libfbclient2 - update to 3.0.14.33856-150200.3.9.1
libib_util-debuginfo - update to 3.0.14.33856-150200.3.9.1
firebird-utils - update to 3.0.14.33856-150200.3.9.1
firebird-server - update to 3.0.14.33856-150200.3.9.1
libib_util-devel - update to 3.0.14.33856-150200.3.9.1
libfbclient2-debuginfo - update to 3.0.14.33856-150200.3.9.1
firebird-server-debuginfo - update to 3.0.14.33856-150200.3.9.1
firebird-utils-debuginfo - update to 3.0.14.33856-150200.3.9.1
libfbclient-devel - update to 3.0.14.33856-150200.3.9.1
firebird-debuginfo - update to 3.0.14.33856-150200.3.9.1

• https://github.com/FirebirdSQL/firebird/security/advisories/GHSA-9884-9qm3-hqch

• Multiple vulnerabilities in Firebird
• SUSE update for firebird