Heap-based buffer overflow in Microsoft SQL Server - CVE-2026-78442
Published: September 8, 2026
Vulnerability identifier: #VU147821
CSH Severity: High
CVSS v4: 8.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-78442
CWE-ID: CWE-122
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to a boundary error in Windows OLE DB. A remote attacker can trick a victim to connect to a malicious server, trigger a heap-based buffer overflow and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
Affected software
Microsoft SQL Server
How to mitigate CVE-2026-78442
Install updates from vendor's website.
Microsoft SQL Server - addressed in versions 14.0.2130.4, 14.0.3550.4, 15.0.2190.7, 15.0.4490.9