CVE-2020-3333 in Application Services Engine
Summary
by MITRE
A vulnerability in the API of Cisco Application Services Engine Software could allow an unauthenticated, remote attacker to update event policies on an affected device. The vulnerability is due to insufficient authentication of users who modify policies on an affected device. An attacker could exploit this vulnerability by crafting a malicious HTTP request to contact an affected device. A successful exploit could allow the attacker to update event policies on the affected device.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 10/21/2020
The vulnerability identified as CVE-2020-3333 resides within the Application Services Engine software ecosystem of Cisco, representing a critical authentication flaw that undermines the security posture of affected network devices. This weakness specifically targets the API interface responsible for managing event policies, creating an avenue for unauthorized modification of critical security configurations. The vulnerability stems from inadequate user authentication mechanisms that fail to properly validate the identity of entities attempting to modify policy settings, effectively allowing any remote attacker to manipulate device configurations without proper authorization.
The technical exploitation of this vulnerability occurs through carefully crafted HTTP requests that target the vulnerable API endpoints within the Application Services Engine software. Attackers can construct malicious requests that bypass normal authentication procedures and directly modify event policies on affected devices. This flaw operates at the application layer, leveraging the software's insufficient validation of API access requests and user credentials. The vulnerability affects Cisco devices running specific versions of the Application Services Engine software, where the API interface lacks proper authentication checks for policy modification operations. This authentication bypass allows attackers to inject malicious policies that could alter network behavior, potentially leading to unauthorized access or service disruption.
The operational impact of CVE-2020-3333 extends beyond simple policy modification, as event policies typically govern how devices respond to network events and security incidents. An attacker who successfully exploits this vulnerability could potentially redirect network traffic, disable security features, or establish persistent access points within the network infrastructure. The remote nature of the attack means that threat actors can exploit this weakness from outside the network perimeter without requiring any initial access credentials, making the vulnerability particularly dangerous for devices exposed to external network traffic. This weakness directly aligns with CWE-287, which addresses improper authentication issues in software systems, and represents a clear violation of the principle of least privilege that should govern all administrative operations within network infrastructure.
Mitigation strategies for this vulnerability require immediate implementation of Cisco's security advisories and software updates that address the authentication weakness in the Application Services Engine API. Network administrators should ensure that affected devices are updated to versions that properly validate user credentials before allowing policy modifications. Additional protective measures include implementing network segmentation to limit access to affected devices, configuring firewalls to restrict HTTP traffic to only trusted sources, and monitoring network logs for suspicious API access patterns. Organizations should also consider implementing network access controls that prevent unauthorized remote access to devices running vulnerable software versions. The ATT&CK framework categorizes this vulnerability under T1078 Valid Accounts and T1566 Phishing, as it enables attackers to maintain persistent access through policy manipulation and could be leveraged as part of broader attack campaigns targeting network infrastructure.