A vulnerability in the ZIP inspection engine of Cisco AsyncOS for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass the engine protection and deliver malicious ZIP files. The vulnerability is due to improper implementation of the logic for analyzing the content of a ZIP file. An attacker could exploit this vulnerability by crafting the ZIP file before sending it through the system. Cisco has confirmed the vulnerability in a security notice and released software updates. An exploit of this vulnerability could allow an attacker to bypass security restrictions on a targeted system, which could be used to send malicious ZIP files to be processed by the system. Processing the malicious ZIP files could be used to conduct further attacks. Cisco indicates through the CVSS score that functional exploit code exists; however, the code is not known to be publicly available.
The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.
To learn about Cisco security vulnerability disclosure policies and publications, see the Security Vulnerability Policy. This document also contains instructions for obtaining fixed software and receiving security vulnerability information from Cisco.
| Version | Description | Section | Status | Date |
| 1.0 | Initial Release | NA | Final | 2014-Oct-14 |
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