VDB-221415 · CVE-2021-32843 · GHSL-2021-054

HyperKit up to 0.20210107 virtio.c vc_cfgread null pointer dereference

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5.0	$0-$5k	0.00

Summaryinfo

A vulnerability was found in HyperKit up to 0.20210107. It has been classified as problematic. The impacted element is the function vc_cfgread of the file virtio.c. Performing a manipulation results in null pointer dereference. This vulnerability is known as CVE-2021-32843. Attacking locally is a requirement. No exploit is available. It is recommended to apply a patch to fix this issue.

Detailsinfo

A vulnerability was found in HyperKit up to 0.20210107. It has been classified as problematic. This affects the function vc_cfgread of the file virtio.c. The manipulation with an unknown input leads to a null pointer dereference vulnerability. CWE is classifying the issue as CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. This is going to have an impact on availability. The summary by CVE is:

HyperKit is a toolkit for embedding hypervisor capabilities in an application. In versions 0.20210107 and prior of HyperKit, `virtio.c` has is a call to `vc_cfgread` that does not check for null which when called makes the host crash. This issue may lead to a guest crashing the host causing a denial of service. This issue is fixed in commit df0e46c7dbfd81a957d85e449ba41b52f6f7beb4.

The weakness was published 02/18/2023 as GHSL-2021-054. It is possible to read the advisory at securitylab.github.com. This vulnerability is uniquely identified as CVE-2021-32843 since 05/12/2021. Technical details of the vulnerability are known, but there is no available exploit.

Applying the patch df0e46c7dbfd81a957d85e449ba41b52f6f7beb4 is able to eliminate this problem. The bugfix is ready for download at github.com.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Name

HyperKit

Version

0.20210107

License

open-source

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.0
VulDB Meta Temp Score: 5.0

VulDB Base Score: 3.3
VulDB Temp Score: 3.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CNA Base Score: 6.2
CNA Vector (GitHub, Inc.): 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: df0e46c7dbfd81a957d85e449ba41b52f6f7beb4

Timelineinfo

05/12/2021 🔍
02/18/2023 +647 days 🔍
02/18/2023 +0 days 🔍
03/18/2023 +28 days 🔍

Sourcesinfo

Advisory: GHSL-2021-054
Status: Confirmed

CVE: CVE-2021-32843 (🔍)
GCVE (CVE): GCVE-0-2021-32843
GCVE (VulDB): GCVE-100-221415

Entryinfo

Created: 02/18/2023 08:06
Updated: 03/18/2023 16:12
Changes: 02/18/2023 08:06 (52), 03/18/2023 16:12 (11)
Complete: 🔍
Cache ID: 216::103