CVE-2021-4011: 
Rocky Linux vulnerability analysis and mitigation

CVE-2021-4011 is a security vulnerability discovered in xorg-x11-server versions before 21.1.2 and before 1.20.14. The vulnerability involves an out-of-bounds access that can occur in the SwapCreateRegister function within the Record extension of the X.Org X server (Xorg Announce, NVD).

The vulnerability stems from improper validation of request lengths in the handlers for the RecordCreateContext and RecordRegisterClients requests of the Record extension, which can lead to out-of-bounds memory write. The vulnerability has been assigned a CVSS v3.1 base score of 7.8 (HIGH) with the vector string CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H (NetApp Advisory).

The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability. When successfully exploited, it can lead to local privilege escalation on systems where the X server is running with privileged access and remote code execution for ssh X forwarding sessions (Xorg Announce).

The vulnerability has been fixed in xorg-x11-server versions 21.1.2 and 1.20.14. The fix was implemented through a patch (commit e56f61c79fc3cee26d83cda0f84ae56d5979f768) in the xorg server git repository. Users are advised to upgrade to the patched versions (Xorg Announce).