Overview
A critical input validation vulnerability, identified as CVE-2025-66399, has been discovered in Cacti, an open-source network monitoring and fault management framework. This flaw affects versions prior to 1.2.29 and stems from improper handling of SNMP community strings during device configuration. An authenticated user can inject malicious content, potentially leading to command execution on the Cacti server.
Technical Details
The vulnerability lies within the SNMP device configuration functionality of Cacti. Specifically, the application fails to properly sanitize user-supplied SNMP community strings. An attacker with valid Cacti credentials can craft an SNMP community string containing control characters, including newline characters. These maliciously crafted strings are then stored verbatim in the Cacti database.
When Cacti later uses these strings in backend SNMP operations, the injected newline characters can be interpreted by downstream SNMP tools or wrappers as command boundaries. This allows the attacker to inject arbitrary commands that are executed with the privileges of the Cacti process, potentially compromising the entire server.
CVSS Analysis
Currently, a CVSS score has not been assigned to CVE-2025-66399. However, given the potential for command execution, the severity is likely to be high or critical. A proper assessment should consider the impact of potential compromise, which can be severe for systems monitoring sensitive network infrastructure.
Possible Impact
The exploitation of CVE-2025-66399 can have serious consequences, including:
- Arbitrary Command Execution: An attacker can execute commands with the privileges of the Cacti process.
- Data Breach: Sensitive information stored in or accessible by the Cacti server could be compromised.
- System Takeover: Complete control of the Cacti server, potentially leading to further compromise of the network.
- Denial of Service: Malicious commands could disrupt Cacti’s operations, leading to a denial of service.
Mitigation and Patch Steps
The recommended mitigation is to upgrade Cacti to version 1.2.29 or later. This version includes a fix that properly validates and sanitizes SNMP community strings, preventing the injection of malicious control characters.
- Backup Your Cacti Installation: Before upgrading, create a full backup of your Cacti installation, including the database and configuration files.
- Download the Latest Version: Download Cacti version 1.2.29 or later from the official Cacti website.
- Follow the Upgrade Instructions: Carefully follow the upgrade instructions provided in the Cacti documentation. This typically involves replacing the existing Cacti files with the new version and running the database upgrade script.
- Verify the Installation: After upgrading, verify that Cacti is functioning correctly and that the vulnerability has been resolved.
