A vulnerability in Cisco AsyncOS for the Cisco Web Security Appliance (WSA) when the software handles a specific HTTP response code could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an appliance because the appliance runs out of system memory.
The vulnerability occurs because the software does not free client and server connection memory and system file descriptors when a certain HTTP response code is received in the HTTP request. An attacker could exploit this vulnerability by sending a crafted HTTP request to the affected device. An exploit could allow the attacker to cause a DoS condition because the appliance runs out of system memory. When this happens, the device can no longer accept new incoming connection requests.
Cisco has released software updates that address this vulnerability. A workaround that addresses this vulnerability is also available.
from SecurityFocus Vulnerabilities http://ift.tt/1OA5JDR
Bugtraq: Cisco Security Advisory: Cisco Web Security Appliance Connection Denial of Service Vulnerability
Reviewed by 0x000216
on
Wednesday, May 18, 2016
Rating: 5
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Cisco Web Security Appliance Connection Denial of Service Vulnerability
Advisory ID: cisco-sa-20160518-wsa4
Revision 1.0
For Public Release 2016 May 18 16:00 UTC (GMT)
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Summary
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A vulnerability in Cisco AsyncOS for the Cisco Web Security Appliance (WSA) when the software handles a specific HTTP response code could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an appliance because the appliance runs out of system memory.
The vulnerability occurs because the software does not free client and server connection memory and system file descriptors when a certain HTTP response code is received in the HTTP request. An attacker could exploit this vulnerability by sending a crafted HTTP request to the affected device. An exploit could allow the attacker to cause a DoS condition because the appliance runs out of system memory. When this happens, the device can no longer accept new incoming connection requests.
Cisco has released software updates that address this vulnerability. A workaround that addresses this vulnerability is also available.
This advisory is available at the following link:
http://ift.tt/1OA5F6U
co-sa-20160518-wsa4
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