CVE-2015-6427 in FireSIGHT Management Center
Summary
by MITRE
Cisco FireSIGHT Management Center allows remote attackers to bypass the HTTP attack detection feature and avoid triggering Snort IDS rules via an SSL session that is mishandled after decryption, aka Bug ID CSCux53437.
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Analysis
by VulDB Data Team • 07/01/2022
The vulnerability identified as CVE-2015-6427 affects Cisco FireSIGHT Management Center, a critical component in network security infrastructure that provides intrusion detection and prevention capabilities. This flaw represents a significant bypass in the system's HTTP attack detection mechanisms, potentially allowing malicious actors to evade security controls that are designed to identify and block harmful network traffic. The vulnerability specifically targets the handling of SSL sessions within the FireSIGHT environment, creating a pathway for attackers to circumvent Snort IDS rules that would normally detect and prevent such attacks. The issue manifests when the system mishandles SSL sessions after decryption, creating an exploitable condition that undermines the integrity of the security monitoring process.
The technical implementation of this vulnerability stems from improper handling of SSL/TLS session management within the FireSIGHT Management Center's processing pipeline. When SSL sessions are decrypted and processed, the system fails to properly validate or maintain the session state information, allowing attackers to craft malicious traffic patterns that appear benign to the detection mechanisms. This flaw enables attackers to send HTTP-based attacks through encrypted channels without triggering the Snort IDS rules that are specifically configured to identify such malicious activities. The vulnerability operates at the application layer and leverages the inherent complexity of SSL session handling to create a bypass condition that can be exploited remotely without requiring authentication or privileged access to the system.
From an operational perspective, this vulnerability creates a substantial risk to organizations relying on Cisco FireSIGHT Management Center for network security monitoring and intrusion prevention. The ability to bypass HTTP attack detection means that malicious traffic can flow through networks undetected, potentially allowing attackers to establish persistence, exfiltrate data, or deploy additional malware without triggering security alerts. The impact extends beyond immediate exploitation as it undermines the trust in the security monitoring infrastructure, potentially causing organizations to miss legitimate security incidents while allowing actual threats to remain hidden. Organizations with extensive deployments of FireSIGHT Management Center could experience significant security gaps that may persist for extended periods without proper detection or remediation.
Organizations should implement immediate mitigations including applying the vendor-provided security patches and updates that address the SSL session handling flaw. Network administrators should also consider implementing additional monitoring controls and anomaly detection mechanisms to identify unusual traffic patterns that might indicate exploitation attempts. The vulnerability aligns with CWE-295 which addresses improper certificate validation, and it relates to techniques described in the ATT&CK framework under defensive evasion tactics where adversaries attempt to avoid detection by manipulating security controls. Organizations should also review their incident response procedures to ensure they can detect and respond to potential exploitation of this vulnerability, particularly focusing on monitoring for anomalous SSL traffic patterns that might indicate attempts to bypass security controls.