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Questions tagged [waf]

WAF stands for Web Application Layer Firewall. WAF is an application layer firewall that is meant to secure the back end web server by monitoring every HTTP request and response to and from the server.

29
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2answers
4k views

What are possible security problems of enabling HTTP2?

I want to enable HTTP2 for several web servers but I'm worried about the possible security implications. I think about something like: HTTP2 implementations are maybe more error prone than mature ...
24
votes
9answers
6k views

Is a web application firewall necessary if the application is secure?

Recently I've been reading about Web application firewalls and the fact that they protect against most frequent attacks like injections, XSS or CSRF. However, a good application should already be ...
22
votes
1answer
6k views

What is a Web Application Firewall?

What is a Web Application Firewall (WAF) and what are some of the things to look for in an effective one? Why would you deploy a WAF instead of just an IPS?
16
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5answers
3k views

Application security training for developers [closed]

I am trying to establish an application security group within an organization and although there is a plethora of courses for penetration testers, i fail to find an equal amount of training courses ...
16
votes
1answer
2k views

What is a “Trailing Host Header”, and how can I test for it?

My team's been doing some research into WAF protections based upon a WAF testing tool released at Black Hat this year. In the tool, there's a list of hostname evasion tests - that are really just an ...
14
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3answers
4k views

How do I get started using ESAPI WAF?

I've been to the OWASP Enterprise Security API (Java Edition) Google Groups page and found this information missing.
13
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1answer
469 views

WAF Process Creation for Integration of IT and Business

A client has asked me to help them out with their WAF processes. Currently they have a few critical web applications being protected by a couple of WAFs. I have managed to get the WAFs tuned and ready ...
12
votes
2answers
3k views

When performing a PenTest against a WAF-protected site, what should a Pentester know to enhance the Test-Quality?

I'm running a WAF infront of a bunch of Webapps and we have the Apps regulary tested, and we want to improve our Tests by presenting some kind of livelogs to the testers. What informations, from ...
11
votes
4answers
2k views

Why should I use whitelist on a WAF?

I was studying different WAFs, from open-source (such as ModSecurity and NAXSI) to commercial solutions (Imperva, Citrix, Fortinet, etc.). Many people state that having a whitelist-based WAF is far ...
10
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3answers
2k views

Evasion techiques for WAFs

Are there any documented techniques for evading Web application firewall for testing WAF rule configurations?
10
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1answer
498 views

Is there a web application firewall equivalent of virustotal?

I'm wondering if there is a web application firewall (WAF) equivalent of VirusTotal? A site where I can throw for example injection strings, exploits or xss, and it will tell me what the default ...
7
votes
1answer
621 views

Isn't a HIDS, NIDS and WAF complementary?

Assume this scenario: Someone trying to hack a website. Simply put: www.site.com/example.php?=<script>alert(1)</script> A HIDS would see this attempt in Apache's access log, a NIDS would ...
7
votes
5answers
2k views

Master thesis topic - mod_security

I've been playing with mod_security for some time and I'd like somehow to use it in my master thesis. I don't know exactly how this work could be more interesting than describing what mod_security ...
6
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2answers
5k views

How web application firewalls protect application from DDoS attacks?

How to protect a web application from DDoS by the implementation of Web Application firewalls? How effective is this method?
5
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3answers
415 views

Cloud Based WAF

I'm currently evaluating different approaches to implement a web application firewall (WAF) in our architecture. We need the WAF due to PCI DSS. I would prefer using a cloud based WAF (e.g. ...
5
votes
3answers
2k views

Reverse Proxy + WAF

AS part of network design, I am implementing a HTTP Reverse proxy as well as a WAF. The HTTP Proxy, I am thinking about terminating SSL, on either the outer firewall - so the WAF can insect the layer ...
4
votes
2answers
1k views

Why can't persistence XSS be detected by a Web Application Firewall?

This OWASP article mentioned that "Using data validation, only reflected XSS can be detected and prevented, persistent XSS cannot be detected, DOM-based XSS only to be limited degree if part of the ...
4
votes
3answers
655 views

Security implications of WAF revealing internal IP addresses

What are the security implications of a web app firewall/load balancer revealing internal IPs of the web sites behind it to the outside world? A specific example is with F5 products: They use a ...
4
votes
1answer
2k views

Securing a simple webservice against brute-force with mod-security

I want to provide basic defense against brute-force attacks against a simple HTTPS web service. The web service provides a login method (let's say at http://example.org/login) which gets passed a ...
4
votes
3answers
136 views

How useful is the default configuration of ModSecurity for a generic web application?

Scenario: ModSecurity with a "default" or "generic" configuration (like the one that might be provided by shared hosting providers, for example). Generic web application (custom, uncommon, or unknown)...
3
votes
2answers
4k views

Is SSL required for sites hosted behind WAF?

We have a website hosted behind WAF and we will be using HTTPS. The server already has a valid SSL. Do we need to install SSL on WAF servers also?
3
votes
4answers
2k views

Generic defense againt SQL injection

This is a little bit of a rant, but there's a real question at the end. I recently installed a new perl script on a site (which will remain nameless) which failed mysteriously with an error 403. ...
3
votes
1answer
2k views

Mod_security for Apache2 blocks cURL!

I'm trying to get my users lat. and lng. from their address using Google's geocoding API but when mod:security is enabled, it prevents it and the script times out. How can I add an exception by IP or ...
3
votes
1answer
195 views

Better alternative to WAF path whitelisting?

We are managing a WAF which is being used by some applications. Recently I tried to use a Valid URL module to whitelist all the APIs and static resources of an application. Although from the security ...
2
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2answers
300 views

ip-fragmentation and mod_security?

is it possible to use ip-fragmenation (for example with fragroute) to evade mod_security? the idea would be to split a sql-injection- or xss-string into little pieces so it s not recognised.
2
votes
1answer
177 views

What does `&==;` mean with regard to Python Django and bypassing WAFs?

I'm reading someone's slides on bypassing WAFs. &==; : Python Django between parameters; FooBar==POST verb : Apache with PHP; <%I%M%U011e>==<IMG> : IIS ASP Classic; ;/path1 ...
2
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2answers
448 views

Web Application Firewall Rules

For Network Layer Firewalls we have different sort of redundancy and consistency checks like rule shadowing, that can impact the performance of firewall. Do similar kind of checks can be applied on ...
2
votes
1answer
3k views

Does a Web Application Firewall only protect OSI layer 7?

Does a Web Application Firewall (WAF) that is protecting application layer 7, as well protect other layers of the The Open Systems Interconnection (OSI) model?
2
votes
3answers
7k views

What are the main reason to deploy Secure Web Gateway?

As Gartner defined, Secure Web Gateways utilize URL filtering, advanced threat defense, legacy malware protection and application control technologies to defend users from Internet-borne threats, and ...
2
votes
1answer
2k views

WAF testing frameworks

How to test the effectiveness of a Web Application Firewall (WAF), or any other security control that is put in place to protect the web application from being attacked? Currently, what are the ...
2
votes
1answer
143 views

How do I scan a WordPress website which blocks WPSCAN from scanning the website?

I am trying to scan a WordPress website with WPSCAN in Kali Linux but an error is happening. Whenever I start the scan WPSCAN runs for 2-3 min and gets paused and after some time and error comes "the ...
2
votes
2answers
648 views

Protection against command injection with modsecurity

I want to know if modsecurity can protect against command injection and file inclusion. I tested modsecurity with free version and run dvwa which is vulnerable page . But command injection is possible ...
2
votes
2answers
989 views

What is the best material for building an web application firewall? [closed]

I am a newbie in this field, and want to study more about Web Application Firewall. Could anyone tell me any materials or tutorials that I can refer in order to write (build) a Web Application ...
2
votes
1answer
2k views

How to filter https traffic in mod-security WAF?

I'm developing a WAF with good GUI and better log. And my base firewall is mod-security. It works well for http but I also want to work my WAF with https. Any suggestions?
2
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2answers
941 views

Anomaly based web application Firewall

How practical are anomaly based web application firewall in mitigating web based attacks ? Which types of threats do they mitigate against and which don't they? Are their any practical implementation ...
2
votes
3answers
60 views

Web Application Firewall with based on an external decision to detect anomaly

I have a theoretical knowledge about WAF but I do not have knowledge of the tools in the market. I wonder if there are any WAFs that base their decision making through a response from an external ...
2
votes
1answer
485 views

IDS/WAF scenario for 2 web servers

I'm running 2 web servers on 2 different physical hosts at home. They handle both HTTP and HTTPS traffic. I want to protect against web application attacks, but don't want to spend money for ...
1
vote
3answers
2k views

Testing Web Application Firewall Configuration (ModSecurity)

What is the best way of testing my Firewall configuration as i have deployed the Core Rule set provided by the OWASP. But my rule configuration was giving me too many false positives which i resolved ...
1
vote
1answer
728 views

How limit request rate of sqlmap?

How can we restrict the rate of requests made from sqlmap to the foreign server in order to prevent detection from waf?
1
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3answers
8k views

ModSecurity errors related to REQUEST_METHOD HTTP/1.1 and GET

I asked my host to switch on the log file, and it have increasing a lot since then. Its have been increasing with 700 mb for the last week. It’s filled with error messages related to Mod Security. ...
1
vote
1answer
899 views

Using user agent & inputs for SQL injection with ModSecurity WAF

I'm trying to test a challenge website using ModSecurity as a WAF. When I put ' in the user agent I got an error from MySQL. You have an error in your SQL syntax; check the manual that corresponds ...
1
vote
1answer
464 views

Access denied after inserting reflected XSS payload in JavaScript

I am getting multi reflection of my input on a websites page, one of the reflections of my input happens to be inside the <script> tag. The script tag that I just mentioned has it's src ...
1
vote
1answer
95 views

SSL certs signed by different CA

Have a question on SSL certs signed by different CA. in the past, my web server cert is signed with CA1 and it was also imported into the web app firewall for SSL traffic monitoring. Now, I have ...
1
vote
1answer
171 views

How to Develop Waf as Service [closed]

Recently, I've started a my educational project WAF as service. To develop this project as per my view, following things are required: Web Application Firewall is in-line with the web servers; it ...
1
vote
1answer
2k views

WAF SQL evasion using HPF technique

I was reading an article on WAF evasion techniques http://www.slideshare.net/devteev/methods-to-bypass-a-web-application-firewall-eng. The article discusses two techniques HPP (HTTP parameter ...
1
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1answer
373 views

Can a WAF block or detect crafted html file and obfuscated PHP script/shell

What happened was, a friend's company is using dated dot net nuke framework. A html page with 'hacked by xxxx' was found uploaded onto the web server. Upon investigating, it is determined that a ...
1
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2answers
222 views

WAF - How to tell what automated tool is causing alerts

When a WAF is throwing alerts your way is there a tool or way to fingerprint the the script or automated tool the potential attacker is using against the site? What techniques can I use to narrow ...
1
vote
1answer
488 views

WebDAV automatically attempting to connect remotely because of DFS namespace?

I recently bought and Installed a WAF (after much begging). I have a DFS namespace called \\mycompany.com\ which is based on my Active Directory domain name mycompany.com. My website domain is ...
1
vote
1answer
434 views

Web Application Firewall Rule Optimization

Following are the two Rules taken from ModSecurity CRS core Ruleset. These two rules are base Rules for XSS attacks. If we look at these two rules their variables and actions are same what they differ ...
1
vote
0answers
58 views

WAF is set to Alert, not block. We are seeing thousands of XSS and SQL Injection attacks. How can I tell if any were actually successful?

I'm pretty inexperienced with WAFs and the events/alerts it generates. I'm wondering how I can tell if any of those were successful? For example, in the last 24 hours we saw over 50K alerts/events ...