Cisco Bug: CSCur07907 - Cisco Web Security Appliance (WSA) DNS Resolution Vulnerability
Feb 13, 2018
- Cisco Web Security Appliance
Known Affected Releases
Symptom: A vulnerability in Domain Name Service (DNS) resolution function of the Cisco Web Security Appliance (WSA) could allow an unauthenticated, remote attacker to cause a partial denial of service (DoS) condition due to DNS name resolution failing through the device. The vulnerability is due to the handling of DNS requests awaiting a DNS response when new, incoming DNS requests are received. An attacker could exploit this vulnerability by sending TCP proxy traffic to the WSA at a high rate. An exploit could allow the attacker to cause a partial DoS condition because DNS name resolution fails which results in the client receiving a HTTP 503 ''Service Unavailable'' error. Conditions: Device running with default configuration running an affected version of software.
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Bug Details Include
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