CVE-2021-3656
KVM AMD SVM Nested Virtualization Guest-to-Host Escape Vulnerability
Description
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 "virt_ext" field, this issue could allow a malicious L1 to disable both VMLOAD/VMSAVE intercepts and VLS (Virtual VMLOAD/VMSAVE) 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.
INFO
Published Date :
March 4, 2022, 7:15 p.m.
Last Modified :
Jan. 19, 2023, 3:53 p.m.
Source :
[email protected]
Remotely Exploitable :
No
Impact Score :
6.0
Exploitability Score :
2.0
Public PoC/Exploit Available at Github
CVE-2021-3656 has a 2 public PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
Affected Products
The following products are affected by CVE-2021-3656
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2021-3656.
| URL | Resource |
|---|---|
| https://bugzilla.redhat.com/show_bug.cgi?id=1983988 | Issue Tracking Third Party Advisory |
| https://git.kernel.org/pub/scm/virt/kvm/kvm.git/commit/?id=c7dfa4009965a9b2d7b329ee970eb8da0d32f0bc | Patch Third Party Advisory |
| https://github.com/torvalds/linux/commit/c7dfa4009965a9b2d7b329ee970eb8da0d32f0bc | Patch Third Party Advisory |
| https://www.openwall.com/lists/oss-security/2021/08/16/1 | Mailing List Third Party Advisory |
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
None
C
Map Vulnerabilities into Different Layers of the Container Image
Python
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2021-3656 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-3656 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by [email protected]
May. 14, 2024
Action Type Old Value New Value -
Reanalysis by [email protected]
Jan. 19, 2023
Action Type Old Value New Value Changed CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.13 up to (excluding) 5.14 *cpe:2.3:o:linux:linux_kernel:5.14:-:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.14:rc1:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.14:rc2:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.14:rc3:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.14:rc4:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.14:rc5:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.14:rc6:*:*:*:*:*:* OR *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.13 up to (excluding) 4.14.245 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.15 up to (excluding) 4.19.205 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.20 up to (excluding) 5.4.142 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.5 up to (excluding) 5.10.60 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.11 up to (excluding) 5.13.12 *cpe:2.3:o:linux:linux_kernel:5.14:-:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.14:rc1:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.14:rc2:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.14:rc3:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.14:rc4:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.14:rc5:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.14:rc6:*:*:*:*:*:* -
Initial Analysis by [email protected]
Mar. 10, 2022
Action Type Old Value New Value Added CVSS V2 NIST (AV:L/AC:L/Au:N/C:C/I:C/A:C) Added CVSS V3.1 NIST AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H Changed Reference Type https://bugzilla.redhat.com/show_bug.cgi?id=1983988 No Types Assigned https://bugzilla.redhat.com/show_bug.cgi?id=1983988 Issue Tracking, Third Party Advisory Changed Reference Type https://git.kernel.org/pub/scm/virt/kvm/kvm.git/commit/?id=c7dfa4009965a9b2d7b329ee970eb8da0d32f0bc No Types Assigned https://git.kernel.org/pub/scm/virt/kvm/kvm.git/commit/?id=c7dfa4009965a9b2d7b329ee970eb8da0d32f0bc Patch, Third Party Advisory Changed Reference Type https://github.com/torvalds/linux/commit/c7dfa4009965a9b2d7b329ee970eb8da0d32f0bc No Types Assigned https://github.com/torvalds/linux/commit/c7dfa4009965a9b2d7b329ee970eb8da0d32f0bc Patch, Third Party Advisory Changed Reference Type https://www.openwall.com/lists/oss-security/2021/08/16/1 No Types Assigned https://www.openwall.com/lists/oss-security/2021/08/16/1 Mailing List, Third Party Advisory Added CWE NIST CWE-862 Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.13 up to (excluding) 5.14 *cpe:2.3:o:linux:linux_kernel:5.14:-:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.14:rc1:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.14:rc2:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.14:rc3:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.14:rc4:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.14:rc5:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.14:rc6:*:*:*:*:*:* Added CPE Configuration OR *cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* *cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* Added CPE Configuration AND OR *cpe:2.3:a:redhat:software_collections:-:*:*:*:*:*:*:* OR cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:* Added CPE Configuration OR *cpe:2.3:a:redhat:openstack:13:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_desktop:7.0:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_eus:8.1:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_eus:8.2:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_eus:8.4:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems:7.0:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems:8.0:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems_eus:8.1:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems_eus:8.2:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems_eus:8.4:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_for_power_big_endian:7.0:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian:7.0:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian:8.0:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian_eus:8.1:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian_eus:8.2:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian_eus:8.4:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_for_real_time:7:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_for_real_time:8:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_for_real_time_for_nfv:7:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_for_real_time_for_nfv:8:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_for_real_time_for_nfv_tus:8.2:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_for_real_time_for_nfv_tus:8.4:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_for_real_time_tus:8.2:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_for_real_time_tus:8.4:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_for_scientific_computing:7.0:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_server_aus:7.6:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_server_aus:7.7:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_server_aus:8.2:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_server_aus:8.4:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions:7.6:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions:8.1:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions:8.2:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions:8.4:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_server_tus:7.6:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_server_tus:7.7:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_server_tus:8.2:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_server_tus:8.4:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_server_update_services_for_sap_solutions:7.6:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_server_update_services_for_sap_solutions:7.7:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_server_update_services_for_sap_solutions:8.1:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_server_update_services_for_sap_solutions:8.2:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_server_update_services_for_sap_solutions:8.4:*:*:*:*:*:*:* *cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:* Added CPE Configuration AND OR *cpe:2.3:a:redhat:3scale_api_management:2.0:*:*:*:*:*:*:* OR cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:* cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:* Added CPE Configuration AND OR *cpe:2.3:a:redhat:codeready_linux_builder:-:*:*:*:*:*:*:* OR cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:* cpe:2.3:o:redhat:enterprise_linux_eus:8.1:*:*:*:*:*:*:* cpe:2.3:o:redhat:enterprise_linux_eus:8.2:*:*:*:*:*:*:* cpe:2.3:o:redhat:enterprise_linux_eus:8.4:*:*:*:*:*:*:* cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian:8.0:*:*:*:*:*:*:* cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian_eus:8.1:*:*:*:*:*:*:* cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian_eus:8.2:*:*:*:*:*:*:* cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian_eus:8.4:*:*:*:*:*:*:* Added CPE Configuration AND OR *cpe:2.3:a:redhat:virtualization_host:4.0:*:*:*:*:*:*:* OR cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:* cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-3656 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2021-3656
weaknesses.
Exploit Prediction
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.
0.04 }} 0.00%
score
0.05635
percentile