Out-of-bounds write in Oracle VM VirtualBox - CVE-2026-21957
Published: January 20, 2026 / Updated: February 19, 2026
Vulnerability identifier: #VU121765
CSH Severity: Low
CVSS v4: 7.1 [CVSS:4.0/AV:L/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-21957
CWE-ID: CWE-787
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a boundary error within the VMSVGA device. A local user can trigger an out-of-bounds write and execute arbitrary code in the context of the hypervisor.
Affected software
Oracle VM VirtualBox
How to mitigate CVE-2026-21957
Install updates from vendor's website.