CVE-2021-0920
Android Kernel Race Condition Vulnerability
Android Kernel
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
Exploitation status
CISA Known Exploited Vulnerabilities
Listed by CISA on 23 May 2022. US federal agencies were required to remediate it by 13 June 2022.
EPSS — exploitation probability
FIRST puts the probability of exploitation activity in the next 30 days at 0.9%, which is higher than 58.3% of all scored vulnerabilities. EPSS is a forecast of activity, not a measure of severity, and it is rescored daily.
CVSS vector
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
Frequently asked questions
Is CVE-2021-0920 being exploited by ransomware groups?
No ransomware group in this database is currently recorded as exploiting CVE-2021-0920.
What does CVE-2021-0920 affect?
CVE-2021-0920 affects Android Kernel. 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
How severe is CVE-2021-0920?
CVE-2021-0920 is rated MEDIUM with a CVSS base score of 6.4. EPSS puts the probability of exploitation in the next 30 days at 0.9%, higher than 58.3% of all scored vulnerabilities. It is listed in the CISA Known Exploited Vulnerabilities catalog, with a federal remediation deadline of 13 June 2022.
How should organisations respond to CVE-2021-0920?
Apply the vendor patch for Android Kernel as the first priority, and treat any internet-facing instance as the most urgent. Because this vulnerability is associated with ransomware activity, also review whether the affected systems were reachable before patching, rather than assuming that patching alone closes the incident.