A server is a machine running a software daemon that is generally accessed over a network by other machines.

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41
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8answers
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Is physical security less important with disks on a server being encrypted?

If you could get physical access to a server, you could change the root/admin password even if you did not know the current password. However with encrypted disks, I don't think this is possible ...
36
votes
11answers
32k views

DDoS - Impossible to stop?

Is it possible - in theory - to stop1 a DDoS attack of any size? Many people claim it's impossible to stop DDoS attacks and tell me I just shouldn't mess with the wrong people on the internet. But ...
30
votes
13answers
8k views

Is a server infrastructure fundamentally possible which the smartest person can't breach?

TL;DR: Perhaps I've gone overboard with my question's detail, but I wanted to be sure the question was clear since the topic seems very broad. But here it is. The word "smartest" is meant ...
27
votes
3answers
2k views

Does password-protecting a server's BIOS help in securing sensitive data?

I'm running a server of which I protected the BIOS with a password. One doesn't have to enter this password before booting, but before entering the BIOS setup. I just did this from routine. However, ...
20
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6answers
2k views

Is it fundamentally possible to validate that an unmodified version of your client connects to your server?

I'm cross posting this question from Programmers.SE because I think it's equally on-topic here and would like to pose the question to this community as well. This seems like a programming question ...
20
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3answers
2k views

Could a VPS provider have access to the content of their users?

Could a VPS provider like DigitalOcean have access to the content of their users? In their terms of service they do not mention anything related to this question, but could they theoretically have ...
17
votes
4answers
726 views

Global Blackout is a myth?

In order to shut the Internet down, anonymous claimed that putting-down the 13 root DNS servers of the Internet and therefore disabling the HTTP Internet, the most widely used function of the Web, ...
17
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4answers
17k views

Possible to use both private key and password authentication for ssh login?

It seems that they are mutually exclusive, as disabling one gives me the other, and vice versa. Two-factor auth for my ssh servers sounds really nice, so is there any way to accomplish this?
15
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2answers
17k views

Creating user specific authentication methods in SSH

I have configured sshd on an Ubuntu server to use key authentication and it is working fine. I had to disable password authentication for key authentication to work. Server is always accessed via ...
11
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5answers
551 views

Does naming sensitive things discreetly provide protection?

I had a job where a manager said he liked naming servers after places because if they were named descriptively e.g. "passwords database server" they become obvious targets. I sort of generalized this ...
11
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2answers
4k views

How to encrypt data on the server?

I have some data on the server (running Linux) which needs to be encrypted (company policy). This data is being served by an application running on this machine. Now I consider a few possibilities: ...
11
votes
3answers
2k views

Are duplicate SSH server host keys a problem?

I'm doing an assessment of a small network that is using a good bit of virtualization. They have cloned some of their linux machines after generating their SSH server host keys. So the servers all ...
10
votes
1answer
3k views

Check logs for Heartbleed exploit use?

According to articles such as the following, it's apparently possible to check logs for heartbeat requests matching the payloads described in the Heartbleed exploit. Is this something that any server ...
10
votes
1answer
1k views

Git server security

I want to install a Git server for my company. I'm able to get a Windows virtual machine. Now I've been asked to assess its security aspects. I'm lost on how to achieve this goal. As it is a Windows ...
9
votes
3answers
279 views

What is a good source for hardened base configurations

I attended B-Sides in Orlando FL where one of the speakers had mentioned a site which contains hardened configs for popular services such as apache and postfix. The author of these configs is ...
8
votes
5answers
1k views

What Man-made Physical Threat Could Pose Severe Danger to a Server Farm?

I am writing a novel in which a researcher attempts to work against a study he is a part of by purposely sabotaging operations on the research compound. I am wondering if the following is plausible. ...
8
votes
1answer
377 views

Enterprise standard for securing servers.

This must be the most broad question to ask, but through the years, i've come up with my own list of things I so to secure my servers, I follow the obvious steps I could gather online such as, ...
8
votes
1answer
67 views

Once established, are sockets on localhost secure?

Once a TCP socket has been established on localhost, and a connection made using accept, is it possible for a non-privileged user to intercept or modify bytes sent over this connection, or can this ...
8
votes
1answer
1k views

What is the difference between HSM and Key server?

As per PCI-DSS requirements, we have to use either HSM (Hardware Security Module), or Key Server to store the KEK (Key Encryption Key). If I'm storing encrypted DEK (Data Encryption Key) in an App ...
7
votes
4answers
638 views

Bastion host that allows jailed users to SSH but protects private key

Basically, I'm trying to let the user use a private key without having read access to it. Use case: Employee needs to SSH to a server in the data center. There is 1 private key for all servers, ...
7
votes
3answers
3k views

Setting up a security CTF server

I'm looking for resources and information from people who have experience running hacking capture-the-flag challenges. To sum it all up in a simple one-sentence question: How do you set up a server ...
7
votes
2answers
7k views

How safe is the ownCloud encryption in a trusted LAN?

ownCloud looks like a promising locally hosted dropbox alternative. However, it has been pointed out that the encryption is not exactly strong... (The ownCloud team does at least provide a list of ...
7
votes
1answer
3k views

What are the privacy pros and cons of using a public DNS server vs. your own?

Whether I'm using a normal internet connection setup, or tunnelling it through an anonymizing VPN or through TOR, what information of mine is revealed to whatever DNS server that I choose (e.g. Google ...
7
votes
1answer
190 views

“Fix” man in the middle

I've just tried to ssh connect to a server (auth via ssh key), and get the well-known message WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!. I'm the server administrator (but I'm not really a good ...
7
votes
1answer
411 views

Are these SSH passwords of hacked servers?

I have been seeing persistent SSH connection attempts on my computer from a familiar IP address. I got curious and decided to do some Googling on the IP address. Turns out that someone from Indonesia ...
6
votes
1answer
1k views

How can one create one's own anti-virus scan server at home? [closed]

I suppose that every one used a service such as virustotal.com, anubis.iseclab.org, or any other service that could provide the same objective to scan same files. So my question is how can I make ...
6
votes
1answer
287 views

How important is a mysql password for localhost?

We can assume that if an attacker gained access to a web server running mysql that they would be capable of reading the scripts to determine the mysql password. If mysql only responds on localhost, ...
6
votes
3answers
217 views

Will sabotaging a shared web hosting account threaten the security of sibling accounts being that they are shared on the same server?

Will sabotaging a shared web hosting account threaten the security of sibling accounts being that they are shared on the same server? Whether it it be through htaccess setups, posting login ...
6
votes
1answer
8k views

SSL Cert Types and Key Usage

I want to use OpenSSL to create a CSR and submit it to my CA (which uses Microsoft PKI) and receive certificates that can be used for both Server Auth and Client Auth. I'm not clear on a couple of ...
6
votes
5answers
383 views

Does setting a default DROP policy actually improve security?

It seems that the status quo at the moment is to configure firewalls to drop any packets that aren't destined for specifically-opened ports. Many defensive port scanners (such as ShieldsUP!) seem to ...
6
votes
3answers
193 views

How can I ensure safety when literal passwords are required

I have a case at my hands where my server needs to make automated API calls that require authentication. Hence the server will need to know the literal passwords to make those calls. What options do ...
5
votes
6answers
4k views

Is it possible to locate Tor/proxy users? Spam is getting on my nerves

I'm managing a huge forum (over 15k posts and 500 users) and lately some guy uses a VPN (probably) to spam my forums with topics such as: "GAYGAYGAYGAYGAYGAYGAY" "FRIGHT IS GAY HAHAHAHHAA" "ADMINS ...
5
votes
5answers
2k views

Windows 2003 Enterprise infected by Conficker; post-infection problems continue

I used various tools to remove Conficker, and I pretty much succeeded, but I've had recurring problems afterward. It won't update anymore (with the following error message: 0x800706B5) I tried ...
5
votes
2answers
884 views

Using 'sudo vim' to spawn a shell

I've recently read here an answer from a user about the way he hacked a server in a CTF contest. At some point in the description, he said that he did sudo vim and then spawned a shell via VIM using ...
5
votes
2answers
184 views

Could a fake tip that my server is compromised be a social engineering attack?

A little while ago I got the following email from an unknown party (using an @alum.cs.[redacted].edu email address): I'm seeing attack traffic from your Linode. Just a friendly heads up that its ...
5
votes
3answers
364 views

Storing config securely in a semi trusted shared hosting environment

I'm looking for a pattern to store a config file containing sensitive information in a semi trusted hosting environment. Semi trusted in this case meaning I trust them in general, but not with this ...
5
votes
3answers
2k views

How do I improve the physical security of a rack cabinet?

I've got an 8U 19-inch server rack cabinet with two locks - one on the front panel, one on the rear panel. The locks are small cam locks, but the cam part is rather thin and flimsy-looking. I could ...
5
votes
1answer
94 views

Browsers and HTTP Public Key Pinning

The strength of HTTP Public Key Pinning (HPKP) is that the browsers are saving the keys from the HTTP header and can check in the future if the certificate from the website is valid. I have two ...
5
votes
2answers
91 views

Secure Software: How to ensure caller is authentic?

For multiplayer (competitive) games, there is often the issue of needing to detect illegitimate players so they can be denied service. On the other hand, legitimate players should of course be ...
5
votes
1answer
199 views

What is investigated after a possible hack on servers?

My question follows recent news of the Sony hacking incident. I was wondering what type of investigation is conducted by a security firm or the FBI. For example, if the network servers were hacked, ...
5
votes
3answers
1k views

How do I store a user's secret key on a server?

I'm learning about security at the moment and one thing I'd like to try out is having a key server distribute keys to clients that will allow them to securely save and read data locally. My basic ...
5
votes
1answer
78 views

Mail client: Public key pinning

I'm running my own mail server setup: - IMAP: Dovecot - SMTP: Postfix There are 4 clients which retrieve emails via IMAP: - iOS (Default client: Apple Mail) - Android (Default client) - Mac (Default ...
5
votes
1answer
273 views

Does using NAT-T for L2TP / IPsec VPN pose a realistic security risk?

I'm working on upgrading an old Windows RAS server that hosts PPTP VPN. I want to move to a L2TP/IPsec VPN. Due to the firewall appliance we use, the VPN server has to be behind a NAT. This means ...
5
votes
1answer
1k views

How to fuzz on FreeFloat FTP server using SPIKE Fuzzing?

I would to seek help on using SPIKE fuzzer to fuzz an FTP server which I am testing on Freefloat FTP server but do not have idea on how to work on. As I research and tested out many different types of ...
4
votes
2answers
585 views

Preparing for a stolen physical server

What would be the best ways to protect sensitive data stored on a server/drive that gets stolen? The confidentiality of the data is what is important, not retrieving it. Obviously, physical means are ...
4
votes
3answers
2k views

Security of JVM for Server

Using type- and memory-safe languages like Java and Scala for server applications gave me the confidence of having a basic level of security (e.g. compared to C). Now with the recent wave of Oracle ...
4
votes
2answers
86 views

Don’t use a web browser on a server?

After pulling up a Windows Server 2012 instance, I learned that google.com is riskier than I thought: It does the same for microsoft.com. There are instructions to disable "Enhanced Security ...
4
votes
2answers
932 views

What port services can hackers use to break into a server?

I am getting ready to run my first server. I will use ufw to disable every port except port 22 for ssh and port 80 for http. I am curious though. Suppose theoretically I left every port open except ...
4
votes
1answer
689 views

NX bit causes segfault on NOP slide?

doing an assignment for university. We have to exec a shell on a remote server. We're told the NX bit is not set, however, when we redirect to our injected code, the server has a segmentation fault. ...
4
votes
4answers
5k views

Using SYN cookies to perform a DOS attack

In my software security class, we had this question: You are the system administrator for a provider that owns a large network (e.g., at least 64,000 IP addresses). Show how you can use SYN ...