Symantec Messaging Gateway Multiple Security Issues

SUMMARY

Symantec Messaging Gateway (SMG) Appliance management console was susceptible to potential recovery of the AD password by any user with at least authorized read access to the appliance. Also, an admin or support user could potentially escalate a lower-privileged access to root on the appliance by escaping their terminal window to a privileged shell. Successful exploitation could result in elevated access to the SMG Appliance management console or to the network environment.

AFFECTED PRODUCTS

Symantec Messaging Gateway Appliance

---

CVE

|

Affected Version(s)

|

Remediation

CVE-2016-2203

CVE-2016-2204

|

10.6.0-7 and earlier

|

Update to SMG Appliance maintenance release 10.6.1

ISSUES

CVE-2016-2203

---

Severity/CVSSv3:

|

Medium / 7.3 AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H

References:

Impact:

|

Securityfocus: BID: 86137 / NVD: CVE-2016-2203

exposure of stored AD password

Description:

|

(See mitigation section)

CVE-2016-2204

---

Severity/CVSSv3:

|

High / 7.7 AV:L/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:H

References:

Impact:

|

Securityfocus: BID: 86138 / NVD: CVE-2016-2204

Privilege Shell Escape

Description:

|

(See mitigation section)

MITIGATION

Details

Symantec was notified of two privilege escalation issues impacting Symantec's Messaging Gateway Appliance 10.x management console.

An authorized SMG Management console user with at least read-access could potentially locate and decrypt the encrypted AD password stored on the SMG appliance. While encrypted, a determined authorized but malicious user could potentially reverse engineer the encrypted AD password. Recovery of this password would not provide any additional access to the SMG appliance however, it could potentially permit leveraging unauthorized, elevated access to additional resources on the network.

An authorized SMG Management console admin- or support-level user could potentially manipulate code input to the terminal window to escape into a privileged root shell on the console. Successfully gaining a privileged shell could possibly result in unauthorized command execution on or access to the management console and the operating system.

In a typical installation the Symantec Messaging Gateway management interface should not be accessible external to the network environment and access should be restricted to specified users/administrators which would restrict this type of malicious activity to some level of authorized user.

Symantec Response
Symantec product engineers have addressed these issues in SMG Appliance maintenance release 10.6.1. Customers should update to the latest maintenance release as soon as possible to address these issues.

Symantec is not aware of exploitation of or adverse customer impact from this issue.

Update Information

Symantec Mail Gateway Appliance maintenance release 10.6.1 is available through the software update facility.

Best Practices

As part of normal best practices, Symantec strongly recommends the following:

• Restrict access to administrative or management systems to authorized privileged users.

• Restrict remote access, if required, to trusted/authorized systems only.

• Run under the principle of least privilege where possible to limit the impact of potential exploit.

• Keep all operating systems and applications current with vendor patches.

• Follow a multi-layered approach to security. At a minimum, run both firewall and anti-malware applications to provide multiple points of detection and protection to both inbound and outbound threats.

• Deploy network- and host-based intrusion detection systems to monitor network traffic for signs of anomalous or suspicious activity. This may aid in the detection of attacks or malicious activity related to the exploitation of latent vulnerabilities.

ACKNOWLEDGEMENTS

Symantec would like to thank karim reda Fakhir for finding and reporting the access to the stored AD password and working closely with Symantec as it was addressed.

Symantec would like to thank Martin Carpenter with Citco, https://www.citco.com, for reporting the privileged shell escape and working closely with Symantec as it was addressed.

REVISION

4/19/2016 - Modified versions affected to SMG 10.6.0-7 and earlier to properly reflect affected product versions.