A system whose primary function is to deliver web pages on request to clients.

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Is it possible to execute a php script in an image file? [duplicate]

I have an image upload php website. Users can upload images to my website. A user claims he can hack my website using an uploaded image. I opened all the images that he uploaded to my server with ...
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4answers
1k views

Can .htaccess and .htpasswd really protect me?

I want to set up a kind of personal wiki where I can store various sensitive information. However to make it 100% portable and and just plain convineant, I want to put it on the Internet. I'm sure at ...
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4answers
1k views

What is Net-Worm.PHP.Mongiko trying to do?

I found several lines of this request in my web server access log: Source IP Dest IP Request Stat User agent 217.172.190.19 ...
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1answer
962 views

Relative importance of CHROOT for web servers

I have read extremely mixed opinions on the process of chrooting for a web server (non-shared environment). Some people swear by it, yet others say that it isn't as secure as everyone says. Given ...
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2answers
2k views

CloudFlare benefits or drawbacks

Anyone running a webserver would agree, security can be a hustle and tedious job. Recently I came across a service claiming to help with that -- CloudFlare.com. There's plenty of benefits listed on ...
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5answers
7k views

Can I block based on Mac Address?

Incase of dynamic IP's the hacker can work around by taking a new IP or use a Proxy, is it possible to make a ban based on Mac Address ? I want to block at the Webserver level so that unwanted users ...
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2answers
1k views

Securing my web-server / website [closed]

Does anyone know of a comprehensive security guide about important basics / fundamentals which should be done to secure a web-server / website? A web link would do.
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3answers
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Hashcash, is this really used?

I just heard about this term, is it really used? The concept does not seem new, is it used and/or implemented in current technologies?
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4answers
911 views

Combat Apache Killer

Three days ago, KingCope released a simple Perl script to DoS Apache, aptly named Apache Killer. This script launches about 50 threads to request Partial Content from the server with optional GZIP ...
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2answers
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Are there any statistics about webservers and browsers TLS support?

From Hackers break SSL encryption used by millions of sites: The vulnerability resides in versions 1.0 and earlier of TLS, or transport layer security, the successor to the secure sockets layer ...
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4answers
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Webserver logs show someone is trying to hack my site, what should I do?

It looks like someone is trying to hack my site. The following comes from my IIS log files: #Software: Microsoft Internet Information Services 7.5 #Version: 1.0 #Date: 2011-07-03 00:02:39 #Fields: ...
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3answers
687 views

How does an attacker approach a website?

What is a typical mindset and method of approach? What are they likely to try first? At what point does a novice give up versus an expert? How would an automated attack differ from a manual one?
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4answers
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What are the disadvantages of Tor?

I've just started using Tor recently, and I'm not sure exactly what security issues come with the benefits. What should/shouldn't I be worried about (in both everyday normal-web browsing use, in ...
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3answers
324 views

Does concealing server software versions have a notable effect on security?

Web servers can add Server, X-Powered-By and similar headers into HTTP responses. Looks like the consensus is such headers should be removed so that automatic vulnerability scanners don't immediately ...
8
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3answers
702 views

Does hiding version numbers increase my security? [duplicate]

I’m currently trying to improve the security at our work. This sounds very broad, but, for example, I’m penetrating our systems and checking whether servers are vulnerable to certain exploits. As an ...
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3answers
6k views

Is .htaccess protection secure enough?

For the moment we protect a directory on our site with .htaccess and .htpasswd. But I was wondering how secure this is? Are there things I should watch for or can do make it more secure? I don't know ...
8
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2answers
708 views

Isolating Web application hosted on same web server

I am working on a scenario if we have two or more web application hosted on a same server. Let says Web application X is vulnerable so how can i be sure that it will not effect the other web ...
8
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2answers
307 views

Can other customers on shared hosting see requests from/to my site?

I installed a wiki on my shared webhosting (using Apache) account. This wiki is set to private (no read/edit/create rights for unauthorized users) and I'm the only one with an account. The wiki ...
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3answers
557 views

How is “anonymous” getting ahold of all these plain-text passwords

In the last several months there have been several publicized data breaches and public website defacements done by several different hacking groups (which the media loves to group under a single ...
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5answers
861 views

Can I improve website security by storing SSL Keys in DNS? Is DNSSec required? Are threat models available?

In light of recent attacks on SSL/TLS communication, people have been asking about ways to improve the security of SSL webserver communication. Several great solutions have been mentioned in the ...
8
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1answer
205 views

How to force “expensive calculation” when clients connect to my server?

Page 183 of Secrets & Lies on countering denial-of-service attacks: Some researchers have proposed defenses that force the client to perform an expensive calculation to make a connection. ...
8
votes
1answer
381 views

Is Chinese great firewall white or black list based? [closed]

Is a new website blocked by default in China ? I just put online a new website dedicated to chinese people (a working days calculator in China, nothing subversive indeed). However a friend of a ...
8
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5answers
1k views

Securing Debian Apache PHP Server

I have Debian Apache PHP server. I want to secure him after the classic installation process. My usual steps are : List item update all packages remove all unnecessary services like named, portmap, ...
8
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3answers
180 views

What are the risks to a network if a single computer is compromised?

If I open up a dedicated server on my home network to accept incoming connections (HTTP, SSH, etc) and that machine is compromised by an outside attacker, what are the risks to other devices on the ...
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7answers
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Server compromised for 2nd time, cannot locate source of attack

I need some help tracing a vulnerability on my server. For the second time, my server has been compromised with files being replaced with virus-ridden downloads. According to the filesystem dates, ...
7
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2answers
4k views

Do these regex show that I was hacked?

What do these regex commands mean? I found them when I ran the history command: grep --include=\*.php -rnw . -e "update.creditcard" grep --include=\*.php -rnw . -e "e41e" grep --include=\*.php -rnw . ...
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4answers
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Protecting against DOS attacks

Our current site is easily DOS'd. I can perform an AB test against it from Apache and it disappears for about 5-10 minutes. We have been having problems with others DOSing the site - to the point ...
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3answers
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When is it appropriate to SSL Encrypt Database connections?

Let's say I have a web server I setup, and then a database server. However, they are communicating locally and are behind firewall. In my opinion, no SSL is needed here right? The only time to use ...
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2answers
1k views

IIS IP Address Restriction - can I rely on it online?

I've been told that I might have more luck posting here than on Stack Exchange, so here goes: I'm looking for a way to lock down a 3rd party application in IIS. It's a web service, so there's no ...
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4answers
1k views

Does disabling .htaccess improve security?

I have a new WordPress website that has been installed on a server not managed by me. Its admin has enforced a few rules in order to increase security, I'm not entirely aware of its entirety but it ...
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2answers
3k views

Is server hardening with GRSecurity really necessary on the CentOS 6.3 environment?

I consider myself to be reasonably good with IT, however I am relatively fresh at server and system administration. I am a web developer for my company and I have been charged with setting up and ...
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5answers
1k views

Malware code added when site viewed externally

Please see second followup at the bottom! (Now with added real malicious code! ...ish) Prompted by this question, I've noticed that my university's student charity organisation has an interesting ...
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votes
3answers
8k views

How can I block an IP, if I'm getting many http requests in a second?

If some one tried force burst attack on my website, how can I block them? Ideally, I want to block an IP if I have many http/Apache requests in a second.
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4answers
312 views

DNS spoofing of linux distribution repositories

Question(s) Is it possible to "redirect" linux-update-repos via DNS spoofing (e.g. DNS cache poisoning) to a malicious website, so that harmful software (updates) will be installed, when running the ...
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1answer
232 views

Why Apache runs as unprivileged user?

Apache Web server as a security measure relinquishes its system privileges and runs as a normal unprivileged user before accepting clients over a networks. My Question is How this measure prevents ...
7
votes
3answers
491 views

Popularity of Anomaly based IDSes

I've been reading quite some time about anomaly/behavior based IDSes for Web servers. I understand the downsides: possible high false positives, learning phase, constant training. My question is how ...
7
votes
1answer
121 views

Secure HTTP headers

In this article, the example shows ... HttpOnly;Secure However, a check on my server response show ... Secure;HttpOnly This may be a stupid question but, does the order matter? thanks
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1answer
8k views

Server attack attempts, what are they trying to achieve?

Recently, I have got a few 404 errors where the user has requested PHP pages. The URLs are range around the cgi-bin and php versions, eg, /cgi-bin/php4. There is also some query string as part of ...
7
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1answer
604 views

Inconsistencies found in OpenID Provider's HTTP Headers. Which one is the most secure that I should imitate in my STS, and Relying Party?

I'm comparing the HTTP headers of the various providers (LiveID, Google, Yahoo, etc) and notice a broad inconsistency in implementation on the sign in page, sign out page, and subsequent pages. ...
6
votes
3answers
566 views

Appropriate defense for 404s in my logs - persistent web scans from one region

This seems to be a fairly easy question to figure out, but I wanted to make sure. I've got about a thousand entries on one of my web servers with phpmyadmin in the connection criterion, but as I ...
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4answers
2k views

How to identify the HTTP methods supported by a web server?

How can I identify the different HTTP methods supported by a web server, like OPTIONS, TRACE, etc.? I have tried the nc command on Linux. But it doesn't work. It doesn't show me the HTTP methods ...
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3answers
2k views

First steps in preventing DOS attacks

My server is currently being attacked from another server. This is my log: root@my-server:/var/log# tail -f auth.log Feb 19 11:53:08 my-server sshd[3745]: Disconnecting: Too many authentication ...
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3answers
3k views

Advantages of separating Web server from Database

What are the security advantages of installing the database of a web application on a server other than the one containing the web server?
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4answers
3k views

What are the best ways to fake a web server

I was wondering if anyone had some insight into the best way to fake a web service response rather than setting up a web server. For instance, while doing dynamic analysis of malware it's useful to ...
6
votes
2answers
2k views

Known security vulnerabilities in JBoss 4.x.x?

We just had a breach of one of our servers, where an intruder got access using the JBoss account and started running exploit scripts. The server has been taken offline and is being investigated, but ...
6
votes
2answers
2k views

Escalating from Apache shell to root

I have one noob question.I tried to exploit shellshock on my Slackware linux server, but after I connect with reverse shell and User Agent I get that I am apache user and apache user don't have too ...
6
votes
3answers
5k views

How to know if two IP addresses point to the same web server?

Doing some testing against two IP address in the scope I find one web server in each one. Both host what it seems the same web application. They are different public (accessible through Internet) IP ...
6
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3answers
2k views

What's involved in taking over someone else's domain name?

I'm asking this for purely academic reasons. I know that there are domain record lists and whatnot, but I'm trying to understand the exact structure of how DNS works and where someone can potentially ...
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2answers
2k views

How does IP tracking work?

Excuse the naive question (I'm more of a dev than a web-sec person) In the past I've had webservers hacked and usually i've traced it to some random machines which seem to have been compromised (i ...
6
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3answers
430 views

Failed PCI-DSS Compliance | Submitting Evidence

One of our web servers that is managed by a service provider (completely in their control, we have no login access) just failed PCI-DSS vuln. scan by TrustKeeper. The vuln scan detected the box as a ...