CVE-2021-44521
Remote code execution for scripted UDFs
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- High
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
9.1
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.
- Record
CVE-2021-44521- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H - CVSS 2.0
- 8.5 High
AV:N/AC:M/Au:S/C:C/I:C/A:C - Weakness
- CWE-94, CWE-732
- Updated
- 2026-11-02
CVE List No score
Remote code execution for scripted UDFs
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.
- Record
CVE-2021-44521- Weakness
- CWE-94
- Updated
- 2026-11-02
EUVDEUVD-2022-0915 No score
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.
- Record
EUVD-2022-0915- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-8ffc-79xg-29w8
9.1
Apache Cassandra vulnerable to Code Injection due to unsafe configuration
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.
- Record
GHSA-8ffc-79xg-29w8- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-94, CWE-732
- Updated
- 2026-11-02
OSV
9.1
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.
- Record
CVE-2021-44521- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H - Updated
- 2026-11-02
OSVGHSA-8ffc-79xg-29w8
9.1
Apache Cassandra vulnerable to Code Injection due to unsafe configuration
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.
- Record
GHSA-8ffc-79xg-29w8- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-732, CWE-94
- Updated
- 2026-11-02
OSVBIT-cassandra-2021-44521 No score
Remote code execution for scripted UDFs
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.
- Record
BIT-cassandra-2021-44521- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
org.apache.cassandra:cassandra-allMaven |
before 3.0.26 | 3.0.26 |
org.apache.cassandra:cassandra-allMaven |
3.11.0 up to 3.11.12 | 3.11.12 |
org.apache.cassandra:cassandra-allMaven |
4.0.0 up to 4.0.2 | 4.0.2 |
cassandraBitnami |
3.0.0 up to 3.0.26, 3.11.0 up to 3.11.12, 4.0.0 up to 4.0.2 | 3.0.263.11.124.0.2 |
org.apache.cassandra:cassandra-allMaven |
before 3.0.26, plus listed versions 0.7.00.7.0-rc40.7.10.7.100.7.2 Show 45 moreShow less0.7.30.7.40.7.50.7.60.7.6-20.7.70.7.80.7.90.8.00.8.0-beta10.8.0-beta20.8.0-rc10.8.10.8.100.8.20.8.30.8.40.8.50.8.60.8.70.8.80.8.91.0.01.0.0-beta11.0.0-rc11.0.0-rc21.0.11.0.101.0.111.0.121.0.21.0.31.0.41.0.51.0.61.0.71.0.81.0.91.1.01.1.0-beta11.1.0-beta21.1.0-rc11.1.11.1.101.1.11 |
3.0.26 |
org.apache.cassandra:cassandra-allMaven |
3.11.0 up to 3.11.12, plus listed versions 3.11.13.11.103.11.113.11.23.11.3 Show 6 moreShow less3.11.43.11.53.11.63.11.73.11.83.11.9 |
3.11.12 |
org.apache.cassandra:cassandra-allMaven |
4.0.0 up to 4.0.2, plus listed versions 4.0.1 |
4.0.2 |
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| Nuclei | Apache Cassandra Load UDF RCE | |
| PoC in GitHub | WoodenKlaas/CVE-2021-44521 | 2022-02-24 |
| PoC in GitHub | Yeyvo/poc-CVE-2021-44521 | 2022-12-03 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, Nuclei, NVD, OSV, PoC in GitHub |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-44521 is a critical vulnerability (CVSS 9.1) in Apache Cassandra, published February 11, 2022. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 58.9%, the 99th percentile. Fixed in org.apache.cassandra:cassandra-all 3.0.26.
References
lists.apache.org/thread/y4nb9s4co34j8hdfmrshyl09lokm7356
openwall.com/lists/oss-security/2022/02/11/4
jfrog.com/blog/cve-2021-44521-exploiting-apache-cassandra-user-defined-functions-for-remote-code-execution
security.netapp.com/advisory/ntap-20220225-0001
nvd.nist.gov/vuln/detail/CVE-2021-44521
issues.apache.org/jira/browse/CASSANDRA-17352
github.com/advisories/GHSA-8ffc-79xg-29w8
github.com/apache/cassandra
Left out here: 142 versions. The JSON record has them.