Dark Reading is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them.Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Attacks/Breaches

Firewall Wish List

Or, why you should absolutely perform outbound firewall filtering

5:35 PM -- Firewalls aren't just for blocking people from sending traffic to your network. If you've been using them in that way alone, you are missing out on half their value. Firewalls have become ubiquitous, but they are also rarely used to their entire effectiveness.

You've got one, or 50, sitting in your data center, whirring away, doing whatever packet inspection magic they advertise on the box, but what do you really want in a firewall? You want something that stops malicious activity, you want it to protect your assets, you want it to scale, and you want it to be cost effective. Firewalls have been around for many years, yet they are still misused almost as often as they are used.

When people set up a Web server on their network, they typically open port 80 to the world, but they also open it in both directions. The reason for this is completely unexplained in most cases, since it's entirely unneeded, unless the application somehow needs to contact other Websites. That's generally only needed in the case of blog sites, or sites that use other Web services.

Even in the case of Web services it can be locked down so the only sites it can communicate to are those services. Additionally, patch management sites can also be whitelisted. That way the site retains all its functionality but is far more secure. And why? Web servers never need to connect to the Web, however, one of the most frequently used attacks is creating reverse shells over port 80. In other words, the attacker pulls in PHP-include payloads from other Web servers over port 80.

Unless there is a good reason to allow your Website to make outbound requests to other Websites, you can lock your site down quite a bit by performing egress (outbound) firewall filtering. If you aren't doing it, your network administrators aren't giving you your money's worth. If they haven't done this yet, you may want to revisit your network security architecture and lock down those sites.

— RSnake is a red-blooded lumberjack whose rants can also be found at Ha.ckers and F*the.net. Special to Dark Reading.

 

Recommended Reading:

Comment  | 
Print  | 
More Insights
Comments
Newest First  |  Oldest First  |  Threaded View
COVID-19: Latest Security News & Commentary
Dark Reading Staff 8/3/2020
Pen Testers Who Got Arrested Doing Their Jobs Tell All
Kelly Jackson Higgins, Executive Editor at Dark Reading,  8/5/2020
New 'Nanodegree' Program Provides Hands-On Cybersecurity Training
Nicole Ferraro, Contributing Writer,  8/3/2020
Register for Dark Reading Newsletters
White Papers
Video
Cartoon Contest
Write a Caption, Win a Starbucks Card! Click Here
Latest Comment: This comment is waiting for review by our moderators.
Current Issue
Special Report: Computing's New Normal, a Dark Reading Perspective
This special report examines how IT security organizations have adapted to the "new normal" of computing and what the long-term effects will be. Read it and get a unique set of perspectives on issues ranging from new threats & vulnerabilities as a result of remote working to how enterprise security strategy will be affected long term.
Flash Poll
The Changing Face of Threat Intelligence
The Changing Face of Threat Intelligence
This special report takes a look at how enterprises are using threat intelligence, as well as emerging best practices for integrating threat intel into security operations and incident response. Download it today!
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2020-12441
PUBLISHED: 2020-08-06
Denial-of-Service (DoS) in Ivanti Service Manager HEAT Remote Control 7.4 due to a buffer overflow in the protocol parser of the ‘HEATRemoteService’ agent. The DoS can be triggered by sending a specially crafted network packet.
CVE-2020-13793
PUBLISHED: 2020-08-06
Unsafe storage of AD credentials in Ivanti DSM netinst 5.1 due to a static, hard-coded encryption key.
CVE-2020-16207
PUBLISHED: 2020-08-06
Advantech WebAccess HMI Designer, Versions 2.1.9.31 and prior. Multiple heap-based buffer overflow vulnerabilities may be exploited by opening specially crafted project files that may overflow the heap, which may allow remote code execution, disclosure/modification of information, or cause the appli...
CVE-2020-16211
PUBLISHED: 2020-08-06
Advantech WebAccess HMI Designer, Versions 2.1.9.31 and prior. An out-of-bounds read vulnerability may be exploited by processing specially crafted project files, which may allow an attacker to read information.
CVE-2020-16213
PUBLISHED: 2020-08-06
Advantech WebAccess HMI Designer, Versions 2.1.9.31 and prior. Processing specially crafted project files lacking proper validation of user supplied data may cause the system to write outside the intended buffer area, which may allow remote code execution, disclosure/modification of information, or ...