Out-of-bounds write in X.org Server - CVE-2021-4011
Published: December 17, 2021 / Updated: December 21, 2021
Vulnerability identifier: #VU59048
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:U/U:Clear
CVE-ID: CVE-2021-4011
CWE-ID: CWE-787
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: X.org
Affected software:
X.org Server
X.org Server
Detailed vulnerability description
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a boundary error in the SwapCreateRegister() function in the Record extension. A local user can send a specially crafted RecordCreateContext and RecordRegisterClients requests, trigger an out-of-bounds write and execute arbitrary code with elevated privileges.
How to mitigate CVE-2021-4011
Install updates from vendor's website.