Cisco Adaptive Security Appliance contains a vulnerability that could allow an unauthenticated, remote attacker to modify the trust of the Certificate Trust List of a remote IP phone. Updates are not available.
A vulnerability in the Phone Proxy function of the Cisco Adaptive Security Appliance (ASA) could allow an unauthenticated, remote attacker to modify the trust of the Certificate Trust List (CTL) of a remote IP phone.
The vulnerability is due to insufficient authentication of the CTL file. An attacker could exploit this vulnerability by injecting a modified CTL file to the phone proxy. An exploit could allow the attacker to impact the entities trusted by the IP phone.
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.
To exploit this vulnerability, an attacker may require access to trusted, internal networks to inject a modified CTL file to the phone proxy of an affected device. This access requirement decreases the likelihood of a successful exploit.
Cisco indicates through the CVSS score that functional exploit code exists; however, the code is not known to be publicly available.
Cisco has released a security notice at the following link: CVE-2014-0738
Customers are advised to consult Cisco bug ID CSCuj66770 for a complete list of affected product versions.
An unauthenticated, remote attacker could exploit this vulnerability to modify the trust of the CTL of a remote IP phone, which could impact the entities trusted by the phone.
The vulnerability is due to insufficient authentication of the CTL file on an affected device.
An unauthenticated, remote attacker could exploit this vulnerability by injecting a modified CTL file to the phone proxy. An exploit could allow the attacker to impact the entities trusted by the IP phone.
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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