cisco-sa-20190501-wsa-dos: Cisco Web Security Appliance Malformed Request Denial of Service Vulnerability

Published May 1, 2019
·
Updated

A vulnerability in the web proxy functionality of Cisco AsyncOS Software for Cisco Web Security Appliance could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper validation of HTTP and HTTPS requests. An attacker could exploit this vulnerability by sending a malformed HTTP or HTTPS request to an affected device. An exploit could allow the attacker to cause a restart of the web proxy process, resulting in a temporary DoS condition.

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: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190501-wsa-dos

Credit

This vulnerability was found during the resolution(a Cisco TAC support case)

Affected Software

1 affected componentFixes available
Cisco AsyncOS Software Major=11.7, <11.7.0-406, =11.5, <11.5.2-020
11.7.0-40611.5.2-020

Event History

May 1, 2019
Advisory Published
via Cisco·04:00 PM

Child vulnerabilities

Contains the following vulnerabilities.

Frequently Asked Questions

1

What is the severity of cisco-sa-20190501-wsa-dos?

The severity of cisco-sa-20190501-wsa-dos is classified as high due to its potential to cause a denial of service condition.

2

How do I fix cisco-sa-20190501-wsa-dos?

To fix cisco-sa-20190501-wsa-dos, you should upgrade to the latest version of Cisco AsyncOS Software that addresses this vulnerability.

3

What devices are affected by cisco-sa-20190501-wsa-dos?

Cisco AsyncOS Software versions 11.5.2-020 and 11.7.0-406 for Cisco Web Security Appliance are affected by cisco-sa-20190501-wsa-dos.

4

Can cisco-sa-20190501-wsa-dos be exploited remotely?

Yes, cisco-sa-20190501-wsa-dos can be exploited by unauthenticated remote attackers.

5

What does cisco-sa-20190501-wsa-dos vulnerability affect?

The cisco-sa-20190501-wsa-dos vulnerability affects the web proxy functionality of Cisco AsyncOS Software.

Contact

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