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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2016.2765 Cisco Email Security Appliance MIME Header Processing Filter Bypass Vulnerability 21 November 2016 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: Cisco Email Security Appliance Publisher: Cisco Systems Operating System: Cisco Impact/Access: Reduced Security -- Remote/Unauthenticated Resolution: Patch/Upgrade CVE Names: CVE-2016-6463 CVE-2016-6462 Original Bulletin: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20161116-esa2 https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20161116-esa1 Comment: This bulletin contains two (2) Cisco Systems security advisories. - --------------------------BEGIN INCLUDED TEXT-------------------- Cisco Security Advisory Cisco Email Security Appliance MIME Header Processing Filter Bypass Vulnerability Medium Advisory ID: cisco-sa-20161116-esa2 First Published: 2016 November 16 16:00 GMT Version 1.0: Final Workarounds: No workarounds available Cisco Bug IDs: CSCuz85823 CVSS Score: Base 5.0, Temporal 4.1 Base 5.0, Temporal 4.1 AV:N/AC:L/Au:N/C:P/I:N/A:N/E:F/RL:OF/RC:C CVE-2016-6463 CWE-20 Summary A vulnerability in the email filtering functionality of Cisco AsyncOS Software for Cisco Email Security Appliances could allow an unauthenticated, remote attacker to bypass Advanced Malware Protection (AMP) filters that are configured for an affected device. The vulnerability is due to improper error handling when malformed Multipurpose Internet Mail Extensions (MIME) headers are present in an email attachment that is sent through an affected device. An attacker could exploit this vulnerability by sending an email message that has a crafted, MIME-encoded file attachment through an affected device. A successful exploit could allow the attacker to bypass AMP filter configurations for the device. There are no workarounds that address this vulnerability. This advisory is available at the following link: http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20161116-esa2 Affected Products Vulnerable Products This vulnerability affects all releases prior to the first fixed release of Cisco AsyncOS Software for both virtual and hardware versions of Cisco Email Security Appliances, if the AMP feature is configured to scan incoming email attachments. To determine whether AMP is configured on a Cisco Email Security Appliance (ESA), administrators can use the Cisco AsyncOS System Administration GUI or the command-line interface (CLI). In the System Administration GUI, choose Security Services > File Reputation and Analysis, and then check the setting for the File Reputation option. In the CLI, issue the ampconfig command and check the value of the File Reputation field in the command output. The following example shows the output of the ampconfig command for an ESA that has AMP configured to scan incoming email attachments: ciscoesa> ampconfig File Reputation: Enabled File Analysis: Enabled File types selected for File Analysis: Microsoft Windows / DOS Executable Appliance Group ID/Name: Not part of any group yet To determine which release of Cisco AsyncOS Software is running on an ESA, administrators can use the version command in the CLI. The following example shows the output of the version command for an ESA running Cisco AsyncOS Software Release 8.5.7-044: ciscoesa> version Current Version =============== Product: Cisco IronPort X1070 Messaging Gateway(tm) Appliance Model: X1070 Version: 8.5.7-044 . . . Note that Cisco provides regular maintenance of products in the Cisco Cloud Email Security (CES) service solution, which includes Cisco Email Security Appliances and Cisco Content Security Management Appliances. Customers can also request a software upgrade by contacting Cisco CES support. 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 Indicators of Compromise Exploitation of this vulnerability could prevent the AMP feature from detecting a malformed MIME attachment as possible malware. The system log file may contain the following log entry: Info: MID 2612684 AMP file reputation verdict : CLEAN Workarounds There are no workarounds that address this vulnerability. Fixed Software For information about fixed software releases, consult the Cisco bug ID at the top of this advisory. 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. Exploitation and Public Announcements 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. URL http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20161116-esa2 Revision History Version Description Section Status Date 1.0 Initial public release. Final 2016-November-16 LEGAL DISCLAIMER 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. - --- Cisco Security Advisory Cisco Email Security Appliance MIME Header Processing Filter Bypass Vulnerability Medium Advisory ID: cisco-sa-20161116-esa1 First Published: 2016 November 16 16:00 GMT Version 1.0: Final Workarounds: No workarounds available Cisco Bug IDs: CSCva13456 CVSS Score: Base 5.0, Temporal 4.1 Base 5.0, Temporal 4.1 AV:N/AC:L/Au:N/C:P/I:N/A:N/E:F/RL:OF/RC:C CVE-2016-6462 CWE-20 Summary A vulnerability in the email filtering functionality of Cisco AsyncOS Software for Cisco Email Security Appliances could allow an unauthenticated, remote attacker to bypass Advanced Malware Protection (AMP) filters that are configured for an affected device. The vulnerability is due to improper error handling when malformed Multipurpose Internet Mail Extensions (MIME) headers are present in an email attachment that is sent through an affected device. An attacker could exploit this vulnerability by sending an email message that has a crafted, MIME-encoded file attachment through an affected device. A successful exploit could allow the attacker to bypass AMP filter configurations for the device. There are no workarounds that address this vulnerability. This advisory is available at the following link: http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20161116-esa1 Affected Products Vulnerable Products This vulnerability affects all releases prior to the first fixed release of Cisco AsyncOS Software for both virtual and hardware versions of Cisco Email Security Appliances, if the AMP feature is configured to scan incoming email attachments. To determine whether AMP is configured on a Cisco Email Security Appliance (ESA), administrators can use the Cisco AsyncOS System Administration GUI or the command-line interface (CLI). In the System Administration GUI, choose Security Services > File Reputation and Analysis, and then check the setting for the File Reputation option. In the CLI, issue the ampconfig command and check the value of the File Reputation field in the command output. The following example shows the output of the ampconfig command for an ESA that has AMP configured to scan incoming email attachments: ciscoesa> ampconfig File Reputation: Enabled File Analysis: Enabled File types selected for File Analysis: Microsoft Windows / DOS Executable Appliance Group ID/Name: Not part of any group yet To determine which release of Cisco AsyncOS Software is running on an ESA, administrators can use the version command in the CLI. The following example shows the output of the version command for an ESA running Cisco AsyncOS Software Release 8.5.7-044: ciscoesa> version Current Version =============== Product: Cisco IronPort X1070 Messaging Gateway(tm) Appliance Model: X1070 Version: 8.5.7-044 . . . Note that Cisco provides regular maintenance of products in the Cisco Cloud Email Security (CES) service solution, which includes Cisco Email Security Appliances and Cisco Content Security Management Appliances. Customers can also request a software upgrade by contacting Cisco CES support. 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 Workarounds There are no workarounds that address this vulnerability. Fixed Software For information about fixed software releases, consult the Cisco bug ID at the top of this advisory. 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. Exploitation and Public Announcements 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. URL http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20161116-esa1 Revision History Version Description Section Status Date 1.0 Initial public release. Final 2016-November-16 LEGAL DISCLAIMER 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. Cisco Security Vulnerability Policy 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. - --------------------------END INCLUDED TEXT-------------------- You have received this e-mail bulletin as a result of your organisation's registration with AusCERT. The mailing list you are subscribed to is maintained within your organisation, so if you do not wish to continue receiving these bulletins you should contact your local IT manager. If you do not know who that is, please send an email to auscert@auscert.org.au and we will forward your request to the appropriate person. NOTE: Third Party Rights This security bulletin is provided as a service to AusCERT's members. As AusCERT did not write the document quoted above, AusCERT has had no control over its content. The decision to follow or act on information or advice contained in this security bulletin is the responsibility of each user or organisation, and should be considered in accordance with your organisation's site policies and procedures. AusCERT takes no responsibility for consequences which may arise from following or acting on information or advice contained in this security bulletin. NOTE: This is only the original release of the security bulletin. It may not be updated when updates to the original are made. If downloading at a later date, it is recommended that the bulletin is retrieved directly from the author's website to ensure that the information is still current. Contact information for the authors of the original document is included in the Security Bulletin above. If you have any questions or need further information, please contact them directly. Previous advisories and external security bulletins can be retrieved from: http://www.auscert.org.au/render.html?cid=1980 =========================================================================== Australian Computer Emergency Response Team The University of Queensland Brisbane Qld 4072 Internet Email: auscert@auscert.org.au Facsimile: (07) 3365 7031 Telephone: (07) 3365 4417 (International: +61 7 3365 4417) AusCERT personnel answer during Queensland business hours which are GMT+10:00 (AEST). On call after hours for member emergencies only. =========================================================================== -----BEGIN PGP SIGNATURE----- Comment: http://www.auscert.org.au/render.html?it=1967 iQIVAwUBWDJPp4x+lLeg9Ub1AQj+PxAApu+FzEtwR4s+HT9CjexGsw62x3/TFDyC 24L/bEb2bndgCLEC+mYjtBZ5OnnKUR6qSTHx29az7JC9WOFBZO8ci1wECPd3wR+g D62HMcNTzkpaPBfEUNopQ5QbivhwQbAZPx3RhO1lEfo0fSvtTvvawoVlANaiAVsG WFg8lBj0tW4x0ro+RdxJKYYGUjf5Y6SPcNydWjwl6uEEyN89TrVF3HlUvaDmfkEQ ammBimW9YZxN46YPrVssM6l80NZlOXm5c55HNJDRy7/vhnf5DNVIj/KDUv2PrkIm etVuUyKaxVaupECTpsANwbdkBq87ATtg1FVPsnZ9KnDZ0UKcStVOZJp5fYmUHGqw kMpK57jVy8Y/PtJaElWn6TOo2vqlaO059DocbHfV/40JCslf+fsDIVNygP2NLRNE g70dP0b02nJWCY71w9/E6rjI1wtrNX2S+c3dz9cX1fgCYLESQ8lTwApLpi8P81d4 o7IQ5VSWPOGgBkSdVUoyrgASAsklhaV6V+OXhZcuWOKMzomBndjG7ockrjkw/LOj x/2xXN6T9q7K+kC4yT2jmIrN3MmxRWZpeNYLOdrmGv/NEZlZR8pRHQzrK5zKIuoh CtcGofe0ugTJrm+h4QW8NyT0KDVFvZ7ILuiw9vH1p45Z1XtbTLryr5X5lXS+gkrZ eR5ddX90Qg8= =Y0IV -----END PGP SIGNATURE-----