CVE-2013-3385 in Web
Summary
by MITRE
The management GUI in the web framework in IronPort AsyncOS on Cisco Web Security Appliance devices before 7.1.3-013, 7.5 before 7.5.0-838, and 7.7 before 7.7.0-602; Email Security Appliance devices before 7.1.5-106 and 7.3, 7.5, and 7.6 before 7.6.3-019; and Content Security Management Appliance devices before 7.9.1-102 and 8.0 before 8.0.0-404 allows remote attackers to cause a denial of service (system hang) via a series of (1) HTTP or (2) HTTPS requests to a management interface, aka Bug IDs CSCzv58669, CSCzv63329, and CSCzv78669.
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Analysis
by VulDB Data Team • 05/17/2021
The vulnerability described in CVE-2013-3385 represents a critical denial of service weakness within the management graphical user interface of Cisco's IronPort AsyncOS platform. This flaw affects multiple appliance types including Web Security Appliances, Email Security Appliances, and Content Security Management Appliances across various software versions. The vulnerability manifests when remote attackers exploit the web framework's handling of management interface requests, specifically through carefully crafted sequences of HTTP or HTTPS requests directed at the administrative interface. The attack vector exploits weaknesses in input validation and request processing mechanisms that fail to properly handle malformed or excessive request patterns, leading to system resource exhaustion and eventual system hang conditions.
The technical implementation of this vulnerability stems from inadequate state management and request processing within the AsyncOS web framework component. When the management interface receives the series of crafted requests, the system fails to properly validate or limit the processing of these inputs, causing the application to enter an infinite loop or consume excessive system resources. This behavior aligns with CWE-400 vulnerability classification, specifically addressing unchecked resource consumption where the system fails to properly limit resource usage through request handling. The vulnerability demonstrates a classic example of how improper input validation can lead to resource exhaustion attacks, where the system becomes unresponsive due to the inability to process legitimate requests while being overwhelmed by malicious input patterns.
The operational impact of this vulnerability extends beyond simple service disruption to potentially compromise the entire security infrastructure provided by these appliances. Organizations relying on these devices for email, web, and content security face significant risks when the management interface becomes unavailable, as administrators lose the ability to monitor, configure, or troubleshoot the security appliances. This creates a window of vulnerability where security policies cannot be enforced, and the organization's network becomes more exposed to threats during the period when the management interface is compromised. The attack requires minimal privileges and can be executed remotely, making it particularly dangerous as it allows adversaries to disrupt security operations without needing physical access or advanced authentication credentials. This aligns with ATT&CK technique T1499.004 which covers network denial of service attacks targeting management interfaces.
Mitigation strategies for this vulnerability should focus on immediate software updates to the affected versions, as Cisco released patches addressing the specific request handling flaws in AsyncOS versions 7.1.3-013, 7.5.0-838, 7.7.0-602, and their respective counterparts across all affected appliance types. Network segmentation should be implemented to limit direct access to management interfaces from untrusted networks, while implementing additional access controls such as IP whitelisting for management access. Organizations should also deploy intrusion detection systems capable of identifying unusual request patterns that may indicate exploitation attempts, and establish monitoring procedures to detect system hang conditions. The vulnerability highlights the importance of maintaining current security patches and implementing proper access controls for management interfaces, as outlined in security frameworks such as NIST SP 800-41 and ISO 27001 controls related to access control and system availability. Regular security assessments should verify that management interfaces are properly hardened and that appropriate monitoring is in place to detect potential exploitation attempts.