Cisco Security Advisory
Click Icon to Copy Verbose Score
AV:N/AC:L/Au:N/C:N/I:P/A:N/E:F/RL:U/RC:C
-
A vulnerability in the content filtering functionality of Cisco AsyncOS Software for Cisco Email Security Appliances could allow an unauthenticated, remote attacker to bypass content filters configured on an affected device. Email that should have been filtered could instead be forwarded by the device.
The vulnerability is due to incorrect validation of protected or encrypted email attachments that are Roshal Archive (RAR) format files. An attacker could exploit this vulnerability by sending an email message that has a crafted RAR file attachment through an affected device. A successful exploit could allow the attacker to bypass content filters that are configured to detect and act upon protected or encrypted email attachments.
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-20161102-esa
-
Vulnerable Products
This vulnerability affects all releases prior to the first fixed release of Cisco AsyncOS Software for Cisco Email Security Appliances, both virtual and hardware appliances, if the software is configured to use a content filter for email attachments that are protected or encrypted. The following example shows the settings for this type of filter:filter: if (encrypted) OR (attachment-protected) { log-entry(''encrypted or protected'');Products Confirmed Not Vulnerable
No other Cisco products are currently known to be affected by this vulnerability.
Cisco has confirmed that this vulnerability does not affect the following products:
- Cisco Content Security Management Appliance, virtual and hardware versions
- Cisco Web Security Appliance, virtual and hardware versions
-
There are no workarounds that address this vulnerability.
-
Cisco provides information about fixed software in Cisco bugs, which are accessible through the Cisco Bug Search Tool.
When considering software upgrades, customers are advised to regularly consult the advisories for Cisco products, which are available from the Cisco Security Advisories and Alerts page, to determine exposure and a complete upgrade solution.
In all cases, customers should ensure that the devices to be upgraded contain sufficient memory and confirm that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, customers are advised to contact the Cisco Technical Assistance Center (TAC) or their contracted maintenance providers.
-
The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.
-
To learn about Cisco security vulnerability disclosure policies and publications, see the Security Vulnerability Policy. This document also contains instructions for obtaining fixed software and receiving security vulnerability information from Cisco.
-
Show LessVersion Description Section Status Date 1.0 Initial public release. — Final 2016-November-02
-
THIS DOCUMENT IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT IMPLY ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. YOUR USE OF THE INFORMATION ON THE DOCUMENT OR MATERIALS LINKED FROM THE DOCUMENT IS AT YOUR OWN RISK. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE THIS DOCUMENT AT ANY TIME.
A standalone copy or paraphrase of the text of this document that omits the distribution URL is an uncontrolled copy and may lack important information or contain factual errors. The information in this document is intended for end users of Cisco products.