What is CVE-2021-4095?

CVE-2021-4095 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10, classified as a NULL Pointer Dereference flaw (CWE-476). CVE-2021-4095 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2021-4095?

CVE-2021-4095 has a CVSS score of 5.5 out of 10, rated Medium severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

Is there a patch available for CVE-2021-4095?

No patch is currently available for CVE-2021-4095. Monitor the NIST NVD and your Linux distribution's security advisories for updates.

Is CVE-2021-4095 actively exploited?

CVE-2021-4095 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is NULL Pointer Dereference (CWE-476)?

The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. See MITRE CWE for full details: https://cwe.mitre.org/data/definitions/476.html

CVE-2021-4095

Medium

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.

Package Linux Kernel

Published 2022-03-10

Last modified 2024-11-21

CVSS version 3.1

Patch available

Awaiting data

CVSS 3.1 score

5.5

out of 10

Medium

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

High

Vector string

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness type

CWE-476

CVE-2021-4095 is a NULL Pointer Dereference vulnerability

What is NULL Pointer Dereference?

The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. Learn more on MITRE CWE

References

The following references provide additional information about CVE-2021-4095 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Lists
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QIOQN7JJNN6ABIDGRSTVZA65MHRLMH2Q/
Lists
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VT6573CGKVK3DU2632VVO5BVM4IU7SBV/
Kernel patch commit
http://www.openwall.com/lists/oss-security/2022/01/17/1
Patch
Kernel patch commit
https://bugzilla.redhat.com/show_bug.cgi?id=2031194
Patch

Details

CVE ID CVE-2021-4095

Severity Medium

CVSS score 5.5 / 10

CVSS version 3.1

Published 2022-03-10

Modified 2024-11-21

KEV No

Patch Awaiting data

Package linux

Frequently asked questions

What is CVE-2021-4095?

CVE-2021-4095 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as a NULL Pointer Dereference flaw (CWE-476) . CVE-2021-4095 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2021-4095?

CVE-2021-4095 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
Is there a patch available for CVE-2021-4095?

No patch is currently available for CVE-2021-4095. Monitor the NIST NVD and your Linux distribution's security advisories for updates.
Is CVE-2021-4095 actively exploited?

No — CVE-2021-4095 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
What is NULL Pointer Dereference (CWE-476)?

The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. View CWE-476 on MITRE CWE →