Vulnerability CVE-2021-4145

Vulnerability Name:

CVE-2021-4145 (CCN-219473)

Assigned:

2021-10-16

Published:

2021-10-16

Updated:

2022-09-28

Summary:

A NULL pointer dereference issue was found in the block mirror layer of QEMU in versions prior to 6.2.0. The `self` pointer is dereferenced in mirror_wait_on_conflicts() without ensuring that it's not NULL. A malicious unprivileged user within the guest could use this flaw to crash the QEMU process on the host when writing data reaches the threshold of mirroring node.

CVSS v3 Severity:

6.5 Medium (CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H)
5.7 Medium (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/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): Changed
Impact Metrics:	Confidentiality (C): None Integrity (I): None Availibility (A): High

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

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

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

Exploitability Metrics:	Attack Vector (AV): Local Attack Complexity (AC): High Privileges Required (PR): Low User Interaction (UI): None
Scope:	Scope (S): Changed
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

7.8 High (CCN CVSS v2 Vector: AV:N/AC:L/Au:N/C:N/I:N/A:C)

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