In Splunk Enterprise versions below 9.1.0.2, 9.0.5.1, and 8.2.11.2, an attacker can inject American National Standards Institute (ANSI) escape codes into Splunk log files that, when a vulnerable terminal application reads them, can potentially, at worst, result in possible code execution in the vulnerable application. This attack requires a user to use a terminal application that supports the translation of ANSI escape codes to read the malicious log file locally in the vulnerable terminal, and to perform additional user interaction to exploit. Universal Forwarder versions 9.1.0.1, 9.0.5, 8.2.11, and lower can be vulnerable in situations where they have management services active and accessible over the network. Universal Forwarder versions 9.0.x and 9.1.x bind management services to the local machine and are not vulnerable in this specific configuration. See SVD-2022-0605 for more information. Universal Forwarder versions 9.1 use Unix Domain Sockets (UDS) for communication, which further reduces the potential attack surface. The vulnerability does not directly affect Splunk Enterprise or Universal Forwarder. The indirect impact on Splunk Enterprise and Universal Forwarder can vary significantly depending on the permissions in the vulnerable terminal application and where and how the user reads the malicious log file. For example, users can copy the malicious file from the Splunk Enterprise instance and read it on their local machine.
The product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not preserved.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Splunk | Splunk | 8.1.0 (including) | 8.1.14 (excluding) |
| Splunk | Splunk | 8.2.0 (including) | 8.2.11 (excluding) |
| Splunk | Splunk | 9.0.0 (including) | 9.0.5 (excluding) |
Improper encoding or escaping can allow attackers to change the commands that are sent to another component, inserting malicious commands instead. Most products follow a certain protocol that uses structured messages for communication between components, such as queries or commands. These structured messages can contain raw data interspersed with metadata or control information. For example, “GET /index.html HTTP/1.1” is a structured message containing a command (“GET”) with a single argument ("/index.html") and metadata about which protocol version is being used (“HTTP/1.1”). If an application uses attacker-supplied inputs to construct a structured message without properly encoding or escaping, then the attacker could insert special characters that will cause the data to be interpreted as control information or metadata. Consequently, the component that receives the output will perform the wrong operations, or otherwise interpret the data incorrectly.