CVE-2021-4095

A NULL pointer dereference was found in the Linux kernel's KVM when dirty ring logging is enabled without an active vCPU context. An unprivileged local attacker on the host may use this flaw to cause a kernel oops condition and thus a denial of service by issuing a KVM_XEN_HVM_SET_ATTR ioctl. This flaw affects Linux kernel versions prior to 5.17-rc1.

CVSS v3.0 5.5 MEDIUM
CVSS v2.0 1.9 LOW

5.5^/10

CVSS v3.0 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

1.9^/10

CVSS v2.0 : LOW

Vector : AV:L/AC:M/Au:N/C:N/I:N/A:P

Exploitability : 3.4 / Impact : 2.9

Access Vector LOCAL

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact PARTIAL

References

Link	Resource
https://bugzilla.redhat.com/show_bug.cgi?id=2031194	Exploit Issue Tracking Patch Third Party Advisory
http://www.openwall.com/lists/oss-security/2022/01/17/1	Exploit Mailing List Patch Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/VT6573CGKVK3DU2632VVO5BVM4IU7SBV/	Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/QIOQN7JJNN6ABIDGRSTVZA65MHRLMH2Q/	Mailing List Third Party Advisory

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Configurations

Configuration 1 (hide)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

Configuration 2 (hide)

OR	cpe:2.3:o:fedoraproject:fedora:34:::::::*
	cpe:2.3:o:fedoraproject:fedora:35:::::::*

Information

Published : 2022-03-10 09:44

Updated : 2022-07-28 11:01

NVD link : CVE-2021-4095

Mitre link : CVE-2021-4095

JSON object : View

CWE

CWE-476

NULL Pointer Dereference

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Products Affected

fedoraproject

fedora

linux

linux_kernel

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