SUMMARY

The Symantec Client Proxy integrated into older versions of Symantec AntiVirus and Symantec Client Security is vulnerable to a buffer overflow.

AFFECTED PRODUCTS

Note: Only the Symantec products indicated above shipped with these components.

ISSUES

Severity

Medium

MITIGATION

Details

Symantec was notified of an ActiveX buffer overflow in the Symantec Client Proxy, CLIproxy.dll. The issue impacts the client-side only, is done under the user account and does not lead to an escalation of privilege. It is possible to craft specific HTML webpages that pass information to proxy without proper boundary checking. 

The impact of this threat requires user interaction to either click on a link directing them to the specially created html website or otherwise be exposed to said HTML in the constraints of a web browser.

Symantec Response

Symantec product engineers have released a fix for this issue in the MR9 update. Symantec recommends all customers apply the latest available update to protect against threats of this nature. 

Symantec is not aware of any exploitation of or adverse customer impact from these issues.

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

ACKNOWLEDGEMENTS

Symantec would like to thank Alexander Polyakov from DSecRG for reporting these issues and coordinating with us while Symantec resolved them.

REFERENCES

BID: Security Focus, http://www.securityfocus.com, has assigned a Bugtraq ID (BID) 38222 to these issues for inclusion in the Security Focus vulnerability database. 

CVE: These issues are candidates for inclusion in the CVE list (http://cve.mitre.org), which standardizes names for security problems. The CVE initiative has assigned CVE-2010-0108 for the Client Proxy Buffer Overflow