Untrusted Pointer Dereference in Windows and Windows Server - CVE-2021-27077
Published: March 9, 2021 / Updated: April 29, 2021
Vulnerability identifier: #VU51284
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2021-27077
CWE-ID: CWE-822
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Microsoft
Affected software:
Windows
Windows Server
Windows
Windows Server
Detailed vulnerability description
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to untrusted pointer dereference in multiple functions within win32kfull.sys driver. A local user can run a specially crafted program to trigger untrusted pointer dereference and execute arbitrary code with SYSTEM privileges.
How to mitigate CVE-2021-27077
Install updates from vendor's website.
Sources
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-27077
- https://www.zerodayinitiative.com/advisories/ZDI-21-403/
- https://www.zerodayinitiative.com/advisories/ZDI-21-482/
- https://www.zerodayinitiative.com/advisories/ZDI-21-501/
- https://www.zerodayinitiative.com/advisories/ZDI-21-500/
- https://www.zerodayinitiative.com/advisories/ZDI-21-499/
- https://www.zerodayinitiative.com/advisories/ZDI-21-498/
- https://www.zerodayinitiative.com/advisories/ZDI-21-497/
- https://www.zerodayinitiative.com/advisories/ZDI-21-496/
- https://www.zerodayinitiative.com/advisories/ZDI-21-495/
- https://www.zerodayinitiative.com/advisories/ZDI-21-494/