CVE-2021-0920

In unix_scm_to_skb of af_unix.c, there is a possible use after free bug due to a race condition. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android kernelAndroid ID: A-196926917References: Upstream kernel

CVSS v3 6.4 MEDIUM
CVSS v2.0 6.9 MEDIUM

6.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 0.5 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

6.9^/10

CVSS v2.0 : MEDIUM

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

Exploitability : 3.4 / Impact : 10.0

Access Vector LOCAL

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact COMPLETE

Integrity Impact COMPLETE

Availability Impact COMPLETE

References

Link	Resource
https://lists.debian.org/debian-lts-announce/2021/12/msg00012.html	Mailing List Third Party Advisory
https://source.android.com/security/bulletin/2021-11-01	Vendor Advisory
https://lists.debian.org/debian-lts-announce/2021/12/msg00012.html	Mailing List Third Party Advisory
https://source.android.com/security/bulletin/2021-11-01	Vendor Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-0920	Third Party Advisory US Government Resource

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	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::::::

Configuration 2 (hide)

cpe:2.3:o:google:android:-:*:*:*:*:*:*:*

Configuration 3 (hide)

cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

History

No history.

Information

Published : 2021-12-15 19:15

Updated : 2025-10-23 14:53

NVD link : CVE-2021-0920

Mitre link : CVE-2021-0920

CVE.ORG link : CVE-2021-0920

JSON object : View

Products Affected

linux

linux_kernel

google

android

debian

debian_linux

CWE

CWE-362

Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

CWE-416

Use After Free

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