How severe is CVE-2021-0920?

CVE-2021-0920 has a CVSS 3.1 base score of 6.4 (MEDIUM). EPSS estimates a 0.9% probability of exploitation in the next 30 days. It is listed in the CISA Known Exploited Vulnerabilities catalog.

CVE-2021-0920: Android Kernel Race Condition Vulnerability

CISA Known Exploited Vulnerabilities

Android Kernel Race Condition Vulnerability is confirmed as actively exploited and is listed in the CISA KEV catalog.

Added to KEV

2022-05-23

Remediation due

2022-06-13

Required action
Apply updates per vendor instructions.

CISA notes
https://nvd.nist.gov/vuln/detail/CVE-2021-0920

Description

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

Severity

CVSS 3.1 · CISA6.4 MEDIUM

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

SSVC · CISA-ADP

Exploitationactive

Automatableno

Technical impacttotal

Exploitation Context

as of October 15, 2026

All KEV statistics→

CISA added CVE-2021-0920 to the KEV catalog 159 days after its CVE record was published.
It is one of 17 Android entries in the CISA KEV catalog, and one of 3 added in 2022.
Its current EPSS score (0.9%) is higher than that of 3% of CISA KEV entries.

Affected Products

Vendor	Product	Affected versions
-	Android	Android kernel

References

2 Links

Mailing lists

[debian-lts-announce] 20211216 [SECURITY] [DLA 2843-1] linux security update

Other references

https://source.android.com/security/bulletin/2021-11-01

Record Details

Published

2021-12-15

Last updated

2025-10-21

Assigner (CNA)

google_android

Credited to

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CVE record data © The MITRE Corporation, used under the CVE Terms of Use. Exploited-in-the-wild data from the CISA Known Exploited Vulnerabilities catalog (CC0). Exploit prediction scores by FIRST EPSS (first.org/epss). This site is not endorsed or certified by MITRE, NVD, CISA, or FIRST.