In Splunk Enterprise versions below 10.0.1, 9.4.4, 9.3.6, and 9.2.8, and Splunk Cloud Platform versions below 9.3.2411.108, 9.3.2408.118 and 9.2.2406.123, a user who holds a role that contains the high-privilege capability change_authentication, could send multiple LDAP bind requests to a specific internal endpoint, resulting in high server CPU usage, which could potentially lead to a denial of service (DoS) until the Splunk Enterprise instance is restarted. See https://help.splunk.com/en/splunk-enterprise/administer/manage-users-and-security/10.0/manage-splunk-platform-users-and-roles/define-roles-on-the-splunk-platform-with-capabilities and https://help.splunk.com/en/splunk-enterprise/administer/manage-users-and-security/10.0/use-ldap-as-an-authentication-scheme/configure-ldap-with-splunk-web#cfe47e31_007f_460d_8b3d_8505ffc3f0dd__Configure_LDAP_with_Splunk_Web for more information.
The product does not properly control the allocation and maintenance of a limited resource.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Splunk | Splunk | 9.2.0 (including) | 9.2.8 (excluding) |
| Splunk | Splunk | 9.3.0 (including) | 9.3.6 (excluding) |
| Splunk | Splunk | 9.4.0 (including) | 9.4.4 (excluding) |
| Splunk | Splunk | 10.0.0 (including) | 10.0.0 (including) |
| Splunk_cloud_platform | Splunk | 9.2.2406 (including) | 9.2.2406.123 (excluding) |
| Splunk_cloud_platform | Splunk | 9.3.2408 (including) | 9.3.2408.118 (excluding) |
| Splunk_cloud_platform | Splunk | 9.3.2411 (including) | 9.3.2411.108 (excluding) |
Mitigation of resource exhaustion attacks requires that the target system either:
The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question.
The second solution is simply difficult to effectively institute – and even when properly done, it does not provide a full solution. It simply makes the attack require more resources on the part of the attacker.