Vulnerability CVE-2021-4032

Vulnerability Name:

CVE-2021-4032 (CCN-217997)

Assigned:

2021-10-18

Published:

2021-10-18

Updated:

2022-01-28

Summary:

A vulnerability was found in the Linux kernel's KVM subsystem in arch/x86/kvm/lapic.c kvm_free_lapic when a failure allocation was detected. In this flaw the KVM subsystem may crash the kernel due to mishandling of memory errors that happens during VCPU construction, which allows an attacker with special user privilege to cause a denial of service. This flaw affects kernel versions prior to 5.15 rc7.

CVSS v3 Severity:

4.4 Medium (CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H)
3.9 Low (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C)

Exploitability Metrics:	Attack Vector (AV): Local Attack Complexity (AC): Low Privileges Required (PR): High User Interaction (UI): None
Scope:	Scope (S): Unchanged
Impact Metrics:	Confidentiality (C): None Integrity (I): None Availibility (A): High

5.5 Medium (CCN CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)
4.8 Medium (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C)

Exploitability Metrics:	Attack Vector (AV): Local Attack Complexity (AC): Low Privileges Required (PR): Low User Interaction (UI): None
Scope:	Scope (S): Unchanged
Impact Metrics:	Confidentiality (C): None Integrity (I): None Availibility (A): High

CVSS v2 Severity:

4.9 Medium (CVSS v2 Vector: AV:L/AC:L/Au:N/C:N/I:N/A:C)

Exploitability Metrics:	Access Vector (AV): Local Access Complexity (AC): Low Authentication (Au): None
Impact Metrics:	Confidentiality (C): None Integrity (I): None Availibility (A): Complete

4.6 Medium (CCN CVSS v2 Vector: AV:L/AC:L/Au:S/C:N/I:N/A:C)

Exploitability Metrics:	Access Vector (AV): Local Access Complexity (AC): Low Athentication (Au): Single_Instance
Impact Metrics:	Confidentiality (C): None Integrity (I): None Availibility (A): Complete