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Cisco Bug: CSCvf36610 - Cisco Web Security Appliance Web Proxy Memory Exhaustion Denial of Service Vulnerability

Last Modified

Aug 30, 2020

Products (1)

  • Cisco Web Security Appliance

Known Affected Releases

10.1.0-204 10.1.1-235 10.5.1-270 10.5.1-296 10.5.2-042 11.0.0-641 9.1.1-074 9.1.2-010 9.1.2-022 9.1.2-039

Description (partial)

A vulnerability in the web proxy functionality of Cisco AsyncOS Software for Cisco Web Security Appliances could allow an unauthenticated, remote attacker to exhaust system memory and cause a denial of service (DoS) condition on an affected system.

The vulnerability exists because the affected software improperly manages memory resources for TCP connections to a targeted device. An attacker could exploit this vulnerability by establishing a high number of TCP connections to the data interface of an affected device via IPv4 or IPv6. A successful exploit could allow the attacker to exhaust system memory, which could cause the system to stop processing new connections and result in a DoS condition. System recovery may require manual intervention.

Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

This advisory is available at the following link:

Please refer to the advisory.
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