Cisco Adaptive Security Appliance contains a vulnerability that could allow an unauthenticated, remote attacker to pass traffic from an untrusted phone through a targeted device. Updates are not available.
A vulnerability in the TFTP request function of the Phone Proxy feature of the Cisco Adaptive Security Appliance (ASA) could allow an unauthenticated, remote attacker to pass traffic from an untrusted phone through the ASA.
The vulnerability is due to a limitation in processing the TFTP request for a configuration file. An attacker could exploit this vulnerability by sending a crafted TFTP request for a phone configuration file. An exploit could allow the attacker to pass traffic from an untrusted phone through the ASA.
Cisco has confirmed the vulnerability in a security notice; however, software updates are not available.
At the time this alert was first published, Cisco ASA versions 9.1(.3) and prior were vulnerable. Later releases of Cisco ASA may also be vulnerable.
Cisco indicates through the CVSS score that proof-of-concept exploit code exists; however, the code is not known to be publicly available.
Cisco has released a security notice at the following link: CVE-2014-0739
Customers are advised to consult Cisco bug ID CSCuj66766 for a complete list of affected product versions.
An unauthenticated, remote attacker could exploit this vulnerability to bypass security restrictions and pass traffic from an untrusted phone through an affected device.
The vulnerability is due to a limitation in processing TFTP requests for a configuration file by the TFTP request function of the Phone Proxy feature of an affected device.
An unauthenticated, remote attacker could exploit this vulnerability by sending a crafted TFTP request for a phone configuration file. An exploit could allow the attacker to pass traffic from an untrusted phone through the ASA.
Administrators are advised to contact the vendor regarding future updates and releases.
Administrators may consider using IP-based access control lists (ACLs) to allow only trusted systems to access the affected systems.
Administrators are advised to allow only trusted users to have network access.
Administrators are advised to monitor affected systems.
The security vulnerability applies to the following combinations of products.
Cisco Adaptive Security Appliance (ASA) Software
9.1 .1, .1.4, .2, .2.8, .3
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