Cisco Web Security Appliances contain a vulnerability that could allow an authenticated, remote attacker to execute arbitrary commands on the underlying operating system with elevated privileges. Updates are available.
A vulnerability in the Security Services function in the web framework code could allow an authenticated, remote attacker to execute arbitrary commands on the underlying operating system with elevated privileges.
The vulnerability is due to a failure to properly sanitize user supplied input that is subsequently utilized to perform an action that leverages the underlying command line interface of the device. An authenticated but unprivileged attacker could exploit this vulnerability by sending a crafted URL to the affected system, or by convincing a valid user to click on a malicious URL. An exploit could allow an attacker with sufficient knowledge to take complete control of the affected device.
Cisco has confirmed the vulnerability in a security advisory and has released software updates.
Cisco Web Security Appliance (WSA) versions prior to 7.1.3-013, 7.1.4-101, 7.5.0-838, and 7.7.0-550 are affected.
To exploit the vulnerability, the attacker may provide a link that directs a user to a malicious site and use misleading language or instructions to persuade the user to follow the link. In addition, authentication is required to exploit the vulnerability. This access requirement could limit 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.
An authenticated, remote attacker could exploit the vulnerability to execute arbitrary commands on a targeted system with elevated privileges. A successful exploit could allow the attacker to cause a complete system compromise.
The vulnerability is due to a failure to properly sanitize user-supplied input processed by the affected software. The vulnerability could be triggered by IPv4 or IPv6 traffic directed to the management IP addresses of the affected system via TCP port 8080 or TCP port 8443.
An authenticated but unprivileged attacker could exploit this vulnerability by sending a crafted URL to the affected system or by convincing a valid user to click a malicious URL. A successful exploit could allow an attacker with sufficient knowledge to take complete control of the affected device.
Administrators are advised to apply the appropriate updates.
Administrators may consider disabling management access to the GUI or restricting IP addresses that can access the management interface as mitigation strategies. Details about these actions are in the security advisories listed in the "Vendor Announcements" section of this alert.
Administrators are advised to monitor affected systems.
Cisco customers with active contracts can obtain updates through the Software Center at the following link: Cisco. Cisco customers without contracts can obtain upgrades by contacting the Cisco Technical Assistance Center at 1-800-553-2447 or 1-408-526-7209 or via e-mail at firstname.lastname@example.org.
The security vulnerability applies to the following combinations of products.
Cisco Web Security Appliance (WSA)
7.1 .0, .1, .2, .3, .4 | 7.5 .0, .1 | 7.7 Base
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