CVE-2021-44521
When running Apache Cassandra with the following configuration: enable_user_defined_functions: true enable_scripted_user_defined_functions: true enable_user_defined_functions_threads: false it is possible for an attacker to execute arbitrary code on the…
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 57.5%, higher than 99% of all known CVEs. Patch or mitigate before the next change window.
Description
When running Apache Cassandra with the following configuration: enable_user_defined_functions: true enable_scripted_user_defined_functions: true enable_user_defined_functions_threads: false it is possible for an attacker to execute arbitrary code on the host. The attacker would need to have enough permissions to create user defined functions in the cluster to be able to exploit this. Note that this configuration is documented as unsafe, and will continue to be considered unsafe after this CVE.
- CVSS 3.1
- 9.1 CRITICALCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
- EPSS
- 57.53% probability · 99th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-94, CWE-732
- Affected
- apache/cassandra
- Source
- security@apache.org
EPSS moved from 57.5% on 24 September 2026 to 57.5% on 26 October 2026. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”.
References
- http://www.openwall.com/lists/oss-security/2022/02/11/4Mailing List, Third Party Advisory
- https://jfrog.com/blog/cve-2021-44521-exploiting-apache-cassandra-user-defined-functions-for-remote-code-execution/Exploit, Mitigation, Third Party Advisory
- https://lists.apache.org/thread/y4nb9s4co34j8hdfmrshyl09lokm7356Issue Tracking, Mailing List, Vendor Advisory
- https://security.netapp.com/advisory/ntap-20220225-0001/Third Party Advisory
- http://www.openwall.com/lists/oss-security/2022/02/11/4Mailing List, Third Party Advisory
- https://jfrog.com/blog/cve-2021-44521-exploiting-apache-cassandra-user-defined-functions-for-remote-code-execution/Exploit, Mitigation, Third Party Advisory
- https://lists.apache.org/thread/y4nb9s4co34j8hdfmrshyl09lokm7356Issue Tracking, Mailing List, Vendor Advisory
- https://security.netapp.com/advisory/ntap-20220225-0001/Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.