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Security Advisories Relating to Symantec Products - Symantec Endpoint Protection Manager 11.x Denial of Service


May 22, 2012

Revision History

5/23/2012 – Added 11.0 RU7(11.0.710x) to affected products
7/5/2012 – Following additional analysis and testing, added all releases of SEP 11.x prior to SEP 11.0 RU7 MP2 to Affected Products matrix



CVSS2 Base Score: 4

Impact: 2.86 Exploitability 7.95

CVSS2 Vector AV: AV:N/AC:L/Au:S/C:N/I:N/A:P

Versions of Symantec Endpoint Protection Manager 11.0 running the Network Threat Protection module on Windows Server 2003 are susceptible to a Denial of Service(DoS).  Successful exploitation could potentially result in the system hosting Symantec Endpoint Protection Manager becoming unresponsive to IIS-based web server requests until restarted.

Affected Products





Symantec Endpoint Protection

All releases of SEP 11.x to include SEP11.0 RU7 MP1


SEP 11 RU7 MP2 or migrate to the latest SEP release


Affected Operating Systems

Operating System

Service Pack Level

Windows Server 2003

Service Pack 2 and below


Products Not Affected



Symantec Endpoint Protection


Symantec Endpoint Protection

11.0 RU7 MP2

NOTE:  This DoS only impacts SEP 11.x running on Windows Server 2003, Service Pack 2 and below

Symantec was notified of a Denial of Service(DoS) within the Symantec Endpoint Protection Manager 11.x and related maintenance packs to include SEP11 RU7 MP1 running on Windows Server 2003 SP2 and below. 

A successful exploitation is possible when using audit tools to aggressively scan the targeted Symantec Endpoint Protection Manager host.  After a period of heavy scanning the Network Threat Protection  module responds to the perceived threat by blocking all subsequent traffic to the server.  This can lead the server to stop serving pages and in some instances can cause excessive resource use which can lead to a hang or crash of the server.

This issue does not impact the security of the Symantec Endpoint Manager, only the availability of the web server components.

Manually restarting the server and/or IIS service will remedy the situation.

Symantec Response
Symantec product engineers verified the reported issues.  Symantec engineers fixed the issues in Symantec Endpoint Protection 11.0.7000 RU7 MP2.

Update Information

Updates will be available through customers’ normal support/download locations.

Best Practices
As part of normal best practices, Symantec strongly recommends:

·         Restrict access to administration or management systems to 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 exploit by threats.

·         Keep all operating systems and applications updated with the latest vendor patches.

·         Follow a multi-layered approach to security. Run both firewall and anti-malware applications, at a minimum, 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 detection of attacks or malicious activity related to exploitation of latent vulnerabilities

Symantec credits Greg Johnson of
Clear Skies Security working through CERT/CC for reporting this issue.



Security Focus, http://www.securityfocus.com, has assigned a Bugtraq ID (BID) 50358  to this issue for inclusion in the Security Focus vulnerability database.

This issue is a candidate for inclusion in the Common Vulnerabilities and Exposures (CVE) list (
http://cve.mitre.org). The CVE initiative has assigned CVE-2012-1821 to this issue.


Symantec takes the security and proper functionality of our products very seriously. As founding members of the Organization for Internet Safety (OISafety), Symantec supports and follows responsible disclosure guidelines.
Symantec has developed a Software Security Vulnerability Management Process document outlining the process we follow in addressing suspected vulnerabilities in our products.
Symantec Corporation firmly believes in a proactive approach to secure software development and implements security review into various stages of the software development process. Additionally, Symantec is committed to the security of its products and services as well as to its customers’ data. Symantec is committed to continually improving its software security process.
This document provides an overview of the current Secure Development Lifecycle (SDLC) practice applicable to Symantec’s product and service teams as well as other software security related activities and policies used by such teams. This document is intended as a summary and does not represent a comprehensive list of security testing and practices conducted by Symantec in the software development process.
Please contact secure@symantec.com if you believe you have discovered a security issue in a Symantec product. A member of the Symantec Software Security team will contact you regarding your submission to coordinate any required response. Symantec strongly recommends using encrypted email for reporting vulnerability information to secure@symantec.com.
The Symantec Software Security PGP key can be found at the following location:
Permission to redistribute this alert electronically is granted as long as it is not edited in any way unless authorized by Symantec Software Security. Reprinting the whole or part of this alert in any medium other than electronically requires permission from secure@symantec.com.
Last modified on: May 22, 2012
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