CVE-2019-12694 in Firepower Threat Defense
Summary
by MITRE
A vulnerability in the command line interface (CLI) of Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, local attacker with administrative privileges to execute commands on the underlying operating system with root privileges. The vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability by executing a specific CLI command that includes crafted arguments. A successful exploit could allow the attacker to execute commands on the underlying OS with root privileges.
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Analysis
by VulDB Data Team • 12/29/2023
The vulnerability identified as CVE-2019-12694 represents a critical command injection flaw within Cisco Firepower Threat Defense software that demonstrates the dangers of inadequate input validation in privileged interfaces. This vulnerability specifically affects the command line interface of FTD software, which serves as the primary administrative gateway for network security device management. The flaw exists in how the system processes user inputs through CLI commands, creating a pathway for malicious execution when properly crafted arguments are passed through the interface. Security researchers have classified this as a privilege escalation vulnerability that leverages the trust relationship between legitimate administrative users and the underlying operating system, making it particularly dangerous in enterprise environments where administrative access is often tightly controlled.
The technical exploitation of CVE-2019-12694 occurs through a specific sequence of CLI commands that bypass normal input sanitization mechanisms. When an authenticated administrator executes a particular command with maliciously constructed arguments, the system fails to properly validate or sanitize the input before passing it to the underlying operating system shell. This insufficient input validation creates a command injection vector that allows arbitrary code execution with the highest level of system privileges. The vulnerability is particularly concerning because it requires only administrative access rather than elevated privileges, meaning that any attacker who can authenticate to the FTD system with administrative credentials can potentially escalate their privileges to root level access. This aligns with CWE-77 and CWE-88 categories that specifically address command injection vulnerabilities where user-supplied data is improperly handled in shell contexts.
The operational impact of this vulnerability extends beyond simple privilege escalation, as it fundamentally compromises the security posture of networks protected by Cisco Firepower devices. An attacker who successfully exploits this vulnerability can execute arbitrary commands with root privileges, potentially leading to complete system compromise, data exfiltration, or the installation of persistent backdoors. The vulnerability affects multiple versions of Cisco Firepower Threat Defense software, making it widespread across enterprise deployments that rely on these security appliances for network protection. Organizations using these devices face significant risk of unauthorized access and potential lateral movement within their networks, as the attacker can leverage the root access to manipulate firewall rules, disable security features, or establish covert communication channels. This vulnerability directly impacts the CIA triad by compromising confidentiality through potential data access, integrity through possible system manipulation, and availability through potential service disruption or denial of access.
Mitigation strategies for CVE-2019-12694 focus primarily on applying official Cisco security patches and updates that address the input validation deficiencies in the FTD CLI interface. Organizations should immediately implement the security advisories provided by Cisco, which typically include code modifications that properly sanitize user inputs before processing them through system commands. Network administrators should also consider implementing additional monitoring controls to detect suspicious CLI activity patterns that might indicate exploitation attempts. The principle of least privilege should be reinforced by limiting administrative access to only necessary personnel and implementing multi-factor authentication for administrative accounts. Security teams should conduct regular audits of administrative access logs and implement behavioral analytics to identify anomalous command execution patterns. This vulnerability underscores the importance of proper input validation practices and aligns with ATT&CK technique T1059.001 for command and scripting interpreter, highlighting the need for defensive measures that protect against both direct command injection and indirect privilege escalation attacks that leverage trusted administrative interfaces.