CVE-2022-33891
Apache Spark Command Injection Vulnerability
Apache Spark
The Apache Spark UI offers the possibility to enable ACLs via the configuration option spark.acls.enable. With an authentication filter, this checks whether a user has access permissions to view or modify the application. If ACLs are enabled, a code path in HttpSecurityFilter can allow someone to perform impersonation by providing an arbitrary user name. A malicious user might then be able to reach a permission check function that will ultimately build a Unix shell command based on their input, and execute it. This will result in arbitrary shell command execution as the user Spark is currently running as. This affects Apache Spark versions 3.0.3 and earlier, versions 3.1.1 to 3.1.2, and versions 3.2.0 to 3.2.1.
Exploitation status
CISA Known Exploited Vulnerabilities
Listed by CISA on 7 March 2023. US federal agencies were required to remediate it by 28 March 2023.
EPSS — exploitation probability
FIRST puts the probability of exploitation activity in the next 30 days at 93.2%, which is higher than 99.8% 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:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Frequently asked questions
Is CVE-2022-33891 being exploited by ransomware groups?
No ransomware group in this database is currently recorded as exploiting CVE-2022-33891.
What does CVE-2022-33891 affect?
CVE-2022-33891 affects Apache Spark. The Apache Spark UI offers the possibility to enable ACLs via the configuration option spark.acls.enable. With an authentication filter, this checks whether a user has access permissions to view or modify the application. If ACLs are enabled, a code path in HttpSecurityFilter can allow someone to perform impersonation by providing an arbitrary user name. A malicious user might then be able to reach a permission check function that will ultimately build a Unix shell command based on their input, and execute it. This will result in arbitrary shell command execution as the user Spark is currently running as. This affects Apache Spark versions 3.0.3 and earlier, versions 3.1.1 to 3.1.2, and versions 3.2.0 to 3.2.1.
How severe is CVE-2022-33891?
CVE-2022-33891 is rated HIGH with a CVSS base score of 8.8. EPSS puts the probability of exploitation in the next 30 days at 93.2%, higher than 99.8% of all scored vulnerabilities. It is listed in the CISA Known Exploited Vulnerabilities catalog, with a federal remediation deadline of 28 March 2023.
How should organisations respond to CVE-2022-33891?
Apply the vendor patch for Apache Spark 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.