What is CVE-2021-3653?

CVE-2021-3653 is a High severity Linux kernel vulnerability with a CVSS score of 8.8 out of 10. CVE-2021-3653 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2021-3653?

CVE-2021-3653 has a CVSS score of 8.8 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.

Is there a patch available for CVE-2021-3653?

No patch is currently available for CVE-2021-3653. Monitor the NIST NVD and your Linux distribution's security advisories for updates.

Is CVE-2021-3653 actively exploited?

CVE-2021-3653 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2021-3653

High

A flaw was found in the KVM's AMD code for supporting SVM nested virtualization. The flaw occurs when processing the VMCB (virtual machine control block) provided by the L1 guest to spawn/handle a nested guest (L2). Due to improper validation of the "int_ctl" field, this issue could allow a malicious L1 to enable AVIC support (Advanced Virtual Interrupt Controller) for the L2 guest. As a result, the L2 guest would be allowed to read/write physical pages of the host, resulting in a crash of the entire system, leak of sensitive data or potential guest-to-host escape. This flaw affects Linux kernel versions prior to 5.14-rc7.

Package Linux Kernel

Published 2021-09-29

Last modified 2024-11-21

CVSS version 3.1

Patch available

Awaiting data

CVSS 3.1 score

8.8

out of 10

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Changed

Confidentiality

High

Integrity

High

Availability

High

Vector string

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

Weakness type

CWE-862

CVE-2021-3653 is classified as CWE-862

See CWE-862 on MITRE CWE for full details on this weakness type.

References

The following references provide additional information about CVE-2021-3653 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Packet Storm
http://packetstormsecurity.com/files/165477/Kernel-Live-Patch-Security-Notice-LSN-0083-1.html

Exploit Third Party Advisory VDB Entry
Debian Security
https://lists.debian.org/debian-lts-announce/2021/10/msg00010.html

Mailing List Third Party Advisory
Debian Security
https://lists.debian.org/debian-lts-announce/2021/12/msg00012.html

Mailing List Third Party Advisory
Kernel patch commit
https://bugzilla.redhat.com/show_bug.cgi?id=1983686
Patch
Kernel patch commit
https://www.openwall.com/lists/oss-security/2021/08/16/1
Patch

Details

CVE ID CVE-2021-3653

Severity High

CVSS score 8.8 / 10

CVSS version 3.1

Published 2021-09-29

Modified 2024-11-21

KEV No

Patch Awaiting data

Package linux

Frequently asked questions

What is CVE-2021-3653?

CVE-2021-3653 is a High severity Linux kernel vulnerability with a CVSS score of 8.8 out of 10 . CVE-2021-3653 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2021-3653?

CVE-2021-3653 has a CVSS score of 8.8 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.
Is there a patch available for CVE-2021-3653?

No patch is currently available for CVE-2021-3653. Monitor the NIST NVD and your Linux distribution's security advisories for updates.
Is CVE-2021-3653 actively exploited?

No — CVE-2021-3653 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.