cisco-sa-20190619-esa-bypass: Cisco Email Security Appliance GZIP Content Filter Bypass Vulnerability
A vulnerability in the GZIP decompression engine of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass configured content filters on the device. The vulnerability is due to improper validation of GZIP-formatted files. An attacker could exploit this vulnerability by sending a malicious file inside a crafted GZIP-compressed file. A successful exploit could allow the attacker to bypass configured content filters that would normally drop the email. 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-20190619-esa-bypass
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Affected Software
Event History
Frequently Asked Questions
What is the severity of cisco-sa-20190619-esa-bypass?
The severity of cisco-sa-20190619-esa-bypass is classified as high.
How do I fix cisco-sa-20190619-esa-bypass?
To mitigate cisco-sa-20190619-esa-bypass, upgrade to a fixed version of Cisco AsyncOS Software as recommended in the security advisory.
Who is affected by cisco-sa-20190619-esa-bypass?
Organizations using Cisco Email Security Appliance with the affected versions of Cisco AsyncOS Software are impacted by cisco-sa-20190619-esa-bypass.
What type of attack does cisco-sa-20190619-esa-bypass facilitate?
cisco-sa-20190619-esa-bypass permits unauthenticated remote attackers to bypass content filters.
Is user authentication necessary to exploit cisco-sa-20190619-esa-bypass?
No, user authentication is not required to exploit cisco-sa-20190619-esa-bypass.