Content related to computer security., i.e. content about policies, mechanisms, etc. needed make sure data is not leaked or corrupted and services available in all circumstances.

learn more… | top users | synonyms

0
votes
1answer
23 views

How can I configure my server to avoid information leakage from the SERVER header of its HTTP response

I have a centos 7 server with apache v2.4.6 php 5.4.16 and OpenSSL 1.0.1e-fips installed. I was just doing a scan to it to see how secure my server is. I found out that my server is giving out ...
1
vote
6answers
162 views

Hiding Password in Shell Scripts

How can I hide a password in shell scripts? There are a number of scripts that are accessing database. If we open the script others also aware the username and password. So if anyone knows how to hide ...
0
votes
1answer
22 views

Strange commands on FTP logs

I'm battling with wordpress security problems and sometimes even I have tried everything my server sends spam by some hacker. I have checked my FTP log and I found this code ...
1
vote
1answer
40 views

How the kernel can prevent a malicious program to operate?

If I write an x86 assembly program that tries to fetch and analyse all the addressable memory space. How the kernel can prevent this operation to be done? I am more familiar with small CPU ...
0
votes
0answers
18 views

How to access boot: invite?

I'd like to simply try a root pawd reset, by entering linux single whan systems display boot: when booting. But my Mint system goes directly to user home prompt. Tks
1
vote
2answers
32 views

Prevent certain lines of a script to run as root

Suppose I am writing a shell script that requires root privileges to run, for example- #!/bin/sh ip -s -s neigh flush all ufw enable How can I prevent certain lines of code to be run as root, i.e. ...
1
vote
1answer
27 views

How to trap an event when a file with a specific content (given by e.g. checksum) was created on the local file system?

I want to implement sort of trip-wire security mechanism, that tracks in real time events when user writes a file with a specific content on hard drive of his workstation (which will be managed by ...
0
votes
0answers
18 views

Encrypt some folder and hide key in Linux

I work on a Debian system (Mint actually). I'd like to encrypt some folders and files, for instance: the one with OpenVPN configuration and keys, and be able to decrypt it on the fly. My problem: ...
3
votes
1answer
84 views
+50

OS X FileVault 2 duress password

I've been attempting to add a custom script to run after the FileVault password is entered on login that will check whether it a 'special password' that will run a script in the background after ...
1
vote
0answers
14 views

shared memory performance and protection from other processes [migrated]

I am trying to implement a JIT compiler (I have very geeky hobbies). I would like to have one main process that keeps some persistent variables, and a second process (that has been compiled ...
2
votes
2answers
31 views

How can I set up a secure LAMP stack on CentOS?

I have been using linux for years, but I need some clarification on what are probably pretty basic principles to how the OS works, but I definitely need clarification due to security concerns. I am ...
2
votes
1answer
54 views

How to Mark Traffic using IPtables?

I'm trying to mark traffic, How shall I write following code in terms of IPtables? /ip firewall mangle> add chain=prerouting src-address=10.1.1.1/32 action=mark-connection \ ...
5
votes
1answer
147 views

SELinux is preventing /opt/google/chrome/nacl_helper from getattr access on the file /etc/passwd

Is this a bug or a real security concern? It appears to have been discussed but I still don't understand why this is happening and what is being done to address the root cause (I am not going to ...
2
votes
1answer
32 views

What is the difference between the FreeBSD flags, immutable and unlink?

What are the differences or similarities among the FreeBSD flags, simmutable/uimmutable and sunlink/uunlink? Reading man chflags, I see these flags: schg, schange, simmutable set the system ...
1
vote
0answers
44 views

nmap doesn't detect opened port [closed]

I'm testing some vulnerabilities on a machine which has the port 22333 opened (it's used as the ssh port, and I can connect to it without any problem and I can get connected as well with the telnet ...
2
votes
1answer
52 views

Using mailx without storing a password

I'm trying to setup mailx to use my Gmail account. I've found a configuration that can send mail successfully but it requires me to store my email password in a configuration file in my home ...
1
vote
2answers
53 views

iptables configuration - ssh connection only from a remote network

I'm trying to configure Iptables of a server in order to permit SSH incoming connections only from a certain network. by the way this is the rule chain : # Drop anything we aren't explicitly ...
1
vote
2answers
29 views

OpenVPN : protect your clients key/cert/conf from being stolen?

I have configured an OpenVPN install. Mode: multiclients 1server. Clients are raspberries. I note how easy it is to steal a rasp, and look in HDD to get key+cert+conf. Copy it on your laptop, and ...
8
votes
3answers
1k views

Is it a good practice to run a daemon under a non-root user account?

I've developed an application that uses NTP to change the network time, to sync two of my computers. It runs as root, since only the latter is allowed to change the time and date on Linux(I guess). ...
0
votes
0answers
10 views

Where to put the ASCII WPA2 Wifi Key in MacOS X?

I tried to make some research about wifi security in our company: So i tried to het WPA2 Wifi key using wifite tool in Kali linux distribution. After the few attempts i get WPS PIN and WPA2 KEY: ...
0
votes
1answer
44 views

What are the best practices for permissions and and methods for generally avoiding using sudo? [closed]

The main point is that I only want one user to have sudo access - really only for use in set up and emergencies. I don't even trust myself with sudo access all the time. Are there best practices ...
1
vote
0answers
43 views

What is the best operating system for beeing anonymous [closed]

Im looking for an anonymous distribution of linux, anyone can help me? Thanks
2
votes
1answer
68 views

How to safely transmit a password over SSH for a remote command to use

On the local server, I have a program that stores the password in the predefined environment variable (SPECIAL_PASSWORD). On the remote server I have a program that reads and uses a password from a ...
1
vote
0answers
24 views

Is there any considerations I should take when running untrusted apps as non-root user?

I have to use an application I don't trust (unstable) and I will run it as a non-privileged user so if something bad happens the damage would be limited to the home folder of that user. I removed ...
0
votes
4answers
61 views

How to track/log commands executed on a shell?

Can commands be written to a logfile before they were executed in any shells? I know there is a patch for ssh to log all commands from ssh sessions, but i want to log even commands executed from a ...
5
votes
1answer
54 views

How to enable random PIDs on Linux?

I'm currently comparing random PID implementation on OpenBSD, FreeBSD and Linux from security perspective. As long as OpenBSD and FreeBSD are concerned, my work is done. However, while the answer ...
0
votes
0answers
40 views

Use sudo as login

I've picked up the habit of using sudo and disallowing root logins. In cases, sudo is integrated with GUI configuration tools that require it. Are there any serious efforts to replace login and ...
4
votes
1answer
91 views

Is it safe for my ssh user to be given passwordless sudo for `apt-get update` and `apt-get upgrade`?

I have an SSH standard user account on my personal server, and it has sudo access (via its password). I ssh in using a public key, so I don't have to type in the account password to log in. Is it ...
2
votes
2answers
82 views

How can I allow SSH and SMTP only using IPTables?

I've got a raspberry pi set up to send me periodic emails. As it's connected to the internet 24/7, I need IPTables set up properly. I want to allow incoming SSH and allow emails to send out on port ...
1
vote
1answer
24 views

Script samba password but securely

I want to script the addition on a samba user and the password. I have seen solutions similar to the one here Piping password to smbpasswd echo -ne "$PASS\n$PASS\n" | smbpasswd -a -s $LOGIN but ...
1
vote
2answers
32 views

How can I create an SSH login that delegates to telnet securely

I'm playing around with the idea of creating a MUD, but one of the down sides is that they use "telnet" which is insecure. I'd like to retain the ability for "anonymous" users to access a specific ...
4
votes
1answer
38 views

Monitoring ARP Poisoning

How to monitor ARP poisoning? These few days my internal website that can be accessed locally has weird image replacing every images on the site for few seconds (it got back to normal after ...
4
votes
0answers
104 views

Unexplained files found in home folder

For background information, I'm running openSUSE 13.2 and KDE 5. Today I found a number of unexplained files and folders in my home folder which state they've been edited 3 days ago. I do not ...
1
vote
0answers
35 views

Allowing sudo kill for remote user for recovery purpose. Security implications?

I'm planning to create user allowed to SSH in and with right to sudo kill in case something disables local terminal/keyboard/display etc. Would probably add ps and/or htop to the list, as well. I ...
1
vote
2answers
76 views

Too many open ports in Debian 8

The IT department has given me 3 virtual servers with Debian 8 for my area, which I will manage (but they have some monitoring tools). Starting Nmap 6.40 ( http://nmap.org ) at 2015-05-11 13:33 ART ...
2
votes
3answers
50 views

Does a Certificate Authority represent my company or a server?

I am setting up my second OpenVPN server with TLS and so I have a question about CA. Should I create a separate CA for each server or use the same? Why? Both servers will cater to the same network ...
4
votes
2answers
110 views

how to prevent a buffer from swap

this question is specific to Unix and Linux. but it is programming and security, too. my program will get a clear password or decryption key by one of a few ways (decrypting a password file, asking ...
1
vote
0answers
25 views

Multiple DHCP Offers - Which is selected? [closed]

I have created a testing scenario in VMWare for a man in the middle attack using DHCP spoofing. It's for a college project. Windows 8 machine bridged to host adapter Kali linux bridged to host ...
0
votes
1answer
42 views

What are the differences between sudo and the use of groups?

I know these are tools used for improving security. But what I would like to know is what they are and how they work?
1
vote
0answers
59 views

Where to put the SElinux policy to allow acpid shutdown the system?

I'm using Centos7 minimal. I've installed acpid and the daemon is running. When I hit the power button, I get the following in /var/log/messages May 2 18:52:53 localhost systemd-logind: Power key ...
0
votes
0answers
60 views

logging wrong passwords in /var/log/auth.log

/var/log/auth.log logs (among other things) failed login attempts to my debian linux. I was wandering if it is possible to ask it to log the password that was used in the failed attempt. This is ...
6
votes
3answers
134 views

What bad things could happen if we don't use sudoedit?

We know it's safer* to use sudoedit, but what bad things can happen if we have the following in sudoers? Cmnd_Alias FOO = /bin/ed, /usr/bin/ed, /usr/bin/vi foouser LOCALHOST = NOPASSWD: NOEXEC: FOO ...
-2
votes
2answers
41 views

Can I restrict the root to a single browser?

I want to be able restrict myself to firefox. I do not want to be able to use any other browser. So if I install chrome or any other browser, I don't want them to work on my Linux machine. Here is ...
0
votes
1answer
40 views

What changes my boot partition and how to prevent it?

As an another countermeasure against security threats I wrote a little script that computes MBR and boot checksum and then compare it to the old one. As long as the computer is running this is OK, but ...
2
votes
1answer
67 views

Understand HMAC authentication in case of site-to-site OpenVPN tunnel

I have a very simple OpenVPN setup where OpenVPN server is started with openvpn --ifconfig 10.10.10.1 10.10.10.2 --dev tun and client is started with openvpn --ifconfig 10.10.10.2 10.10.10.1 --dev tun ...
2
votes
0answers
78 views

Security of sudo not asking for a password after the first time

After using sudo and entering a password to do so, sudo remembers that we have entered a password and we do not have to enter a password the next time we use it. I am concerned about the possibility ...
0
votes
1answer
71 views

How can I study Linux, in and out? [closed]

My team and I will soon begin studying and practicing for the nation-wide Cyber Patriot program. As I'm famed for being our "Linux guy", I would really like to improve my knowledge on the subject. ...
0
votes
1answer
47 views

UNIX Account management

Would like to know if there's some opensource solution aimed to manage and administer system authentication and RSA keys for staff, contractors and clients across the organization. My systems to ...
1
vote
1answer
33 views

Where to verify and review various packages before installing them

I am new to Unix/Linux and corrently setting up a Debian Wheezy server for my domain name. Here and there I find useful tutorial on how to do this-and-that, but I am not sure where I can find a ...
2
votes
1answer
72 views

How to scan a directory with a space in its name with maldet

I'm trying to scan some directories with Linux Malware Detect (command-line command maldet): maldet -a /SOMETHING\ 1/ But I get: maldet(13857): {scan} invalid path /SOMETHING 1/ I've tried ...