Securing Linux systems and applications; understanding Linux security features.

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2
votes
1answer
124 views

Force all user processes to be ptraced

I'm implementing a ptrace based tool for logging system call use. It is much more simple than strace, but I'm doing this so I can learn how these tools work. I'd like to trace all user processes since ...
2
votes
2answers
87 views

What kind of privacy leakage do stuff printed to stdout pose?

1- When a program outputs to stdout, is that normally logged anywhere else? 2- When is it an issue to make a command verbose in printing to stdout instead of working quietly or redirecting to a file? ...
1
vote
1answer
677 views

Pre Installed OpenVAS , light way Linux [closed]

Is there any Pre installed light way OpenVAS Linux distributions Or any light way Linux witch Openvas Tested on it and work properly on that Linux distribution ? I have used Back Track (UBUNTU ...
3
votes
3answers
619 views

Using /usr/bin/passwd as login shell

I have a requirement to set up a SSH tunnel between two hosts. SSH server runs on a Linux host, and the SSH client (PuTTY) runs on a Windows host. I have set up a separate user account (say 'tunnel') ...
1
vote
1answer
437 views

Can exploit vulnerability if program started with gdb, but segfaults if started without gdb

i'm currently trying to exploit a simple program called basic_vuln.c #include <stdio.h> int main(int argc, char** argv) { char buf[64]; strcpy(buf, argv[1]); } I'm using xubuntu ...
-4
votes
1answer
81 views

LUG war games — suggested strategies? [closed]

My LUG on campus once in awhile holds a mock wargames on a VM. I'm trying to figure a way to get root access and make everyone else not be able to have root (king of he hill). I have a few ideas, but ...
6
votes
6answers
1k views

Using linux to combat windows flash drive malware?

I just put an old flash drive which i used with a windows machine into my linux. I noticed many files, mostly exes which were never visible in windows (my windows does not hide hidden files and ...
0
votes
2answers
596 views

How to completely password protect login into Ubuntu 12.10?

I am running Ubuntu 12.10 on my laptop and I would like to make a set up such that without a login password, no one would be able to login into my system. Currently it seems that one can, quite ...
0
votes
3answers
2k views

Retrieve auto saved Skype password from Ubuntu 12.04 LTS

The email address I used to create Skype profile has been disabled and I can't get it back. Unfortunately, I don't remember the Skype password now. As the password is auto saved in my local machine I ...
3
votes
3answers
323 views

Proper Linux user authentication through PAM aware applications

Currently I'm building an authentication system using Linux PAM for a python daemon process. It will need to authenticate remote users from a variety of front-ends against the local user list. ...
32
votes
4answers
3k views

Should I change the default SSH port on linux servers?

Is there any advantage in changing the SSH port, I've seen people do that, but I can't seem to find the reason why. If you have a strong password and/or a certificate, is it useful for anything? ...
1
vote
1answer
194 views

Dual Linux System with Whole Disk Encryption

(This is a continuation of my question on Ask Ubuntu.) My goal is I want to have a Xubuntu/Ubuntu dual boot, with a catch - I want the disk to be fully encrypted with the dm-crypt (native supplied) ...
2
votes
1answer
702 views

Tacacs+ scenario: can I permit user to configure only for one interface and deny others

I'm currently deploying TACACS+ with a Cisco device, I use a TACACS server from here: http://www.shrubbery.net/tac_plus/ My scenario is: I want to permit a user to configure my router but only for a ...
3
votes
2answers
715 views

Is GPG suitable as part of a password manager and generator?

I assume that GPG is very strong to crack, guess, etc. Since I have confidence in GPG, would it be appropriate to use my GPG key as the master key for a password manager or generator?
1
vote
2answers
3k views

Test firewall rules (Linux)

I have a question about how to test the firewall rules. To be more specific, for academic purpose I have to set up a machine which will accept all kind of packets o a specific interface. I added an ...
1
vote
3answers
376 views

How to Detect Zimbra Sniffing Trojan

I am a sys admin of our system, we are running zimbra as email server in our environment. I got the following message from the CEO. "Everytime I send or receive an email - I get a SPAM ads a few ...
2
votes
1answer
206 views

tshark - dump the data section

As the name suggests, im trying to dump the data section of the packet, man would suggest that its something like tshark -r file.pcap -t fields but im not having any luck
1
vote
3answers
834 views

Best practices for firewall hardware

I'm planning to implement a linux based firewall/router with at least 6 x 1Gb NIC's (network with ~300 computers/server with >=8 VLANs) Can anybody recommend hardware best practices (reference to ...
0
votes
1answer
507 views

How configure tomcat 7 SSL to use AES-NI?

My server has AES-NI and I would like tomcat 7 to make use of this but I am not really sure how to make that happen or where to even start looking. I am quite familiar with tomcat administration, and ...
0
votes
2answers
179 views

Tracing root compromises

In regards to the following: 0day Linux/CentOS SSHd Spam Exploit — libkeyutils.so.1.9 SSHD Rootkit There apparently seems to be a bunch of redhat server being backdoored via a library. Does ...
1
vote
1answer
71 views

Does pppd encrypt traffic?

There is pppd program that can be used to create point-to-point conections over various channels (including other network). It supports authentication and compression. But does it encrypt traffic or ...
4
votes
2answers
2k views

Need advice on linux server being hacked

I'm currently trying to find out how one of our centos servers was compromised. We were experiencing malware on our sites. After searching I finally found the malware injecting into the sites. As it ...
9
votes
5answers
1k views

Apache/Linux server, DoS attack from own IP

I have an unusual problem I've been trying to diagnose for a while: It's about a Debian server running a custom compile of apache 2.2 with PHP, Red5, MySQL 5.5 (standard binary), sendmail (distro ...
1
vote
4answers
1k views

Why do I need both root password and user password in Fedora Linux?

I am just now installing (for the first time) a shiny new Fedora 18. I set up a strong root password, installed the whole thing. Now it is asking me to create a user account and a password is ...
5
votes
1answer
156 views

Hidden directory with 0x0d0x0a

Someone has hidden a directory to fool policies on a FTP account. The directory name was 0x0d0x0a. How did the user create a folder with that name? The directory is nearly invisible with ls but ...
0
votes
2answers
302 views

Is there an easy way to secure Apache on debian?

I run an Apache webserver with lots of PHP-sites of several customers. I tried install apache-mod_security2 after this (german) tutorial that is using these rulesets: ...
3
votes
3answers
691 views

Restrict access to a specific directory on Linux

I want to limit access to a single directory on the hard disk (log files) to few processes (log files for a single process for example). All processes run under the same user, so file system access ...
4
votes
3answers
3k views

Wine or sandboxie as sandboxes

I'm looking for a sandbox for Windows. I've looked at sandboxie but I don't know if it delivers what it promises. Is it actually safer to run programs inside sandboxie ? I know a full-blown VM could ...
1
vote
1answer
94 views

set uid for reboot binary & pm-suspend : security hole?

I think all the question is in the title : For the use of my laptop to be more convenient I made a chmod 4755 to /sbin/reboot and /usr/lib/pm-utils/pm-action so I don't have to make a 'sudo' before ...
4
votes
3answers
403 views

Live Linux which does not mount any hard drive in the computer

I am searching for a Linux System which runs from a CD and does not mount any hard drive of the computer. I want to prevent any possiblity to write something on the hard drive of the computer and on ...
0
votes
1answer
799 views

Retrieving saved password from Firefox on Linux [closed]

I know there are ways to get the cookies from browsers in Windows and retrieve and decrypt saved passwords from them. Is there a similar way to do so on CentOS?
6
votes
2answers
5k views

Is it possible to use the aircrack-ng tool to crack a WPA2 Enterprise network?

is this tool (aircrack-ng) capable of cracking into a WPA/WPA2 Enterprise network? This tool has major success cracking the passwords of WEP/WPA networks. If it can, how, but if not, is there another ...
1
vote
2answers
253 views

Linux kernel 3.2 syscalls

Just trying to get the assembler instructions for <__execve> of the code below because i want to build the shell spawn opcode list: #include <stdio.h> int main() { char *happy[2]; ...
6
votes
2answers
193 views

Process authentication for Linux

Is there any possibility to authenticate a running process in Linux to be sure that this is the original/right one? I know that an Linux operating system is only that secure like the way you use it. ...
0
votes
1answer
141 views

Different types of segmentation faults in Linux [closed]

In Linux, when the NX-bit triggers the segmentation fault seems to be "error 15", whereas a more typical error, such as attempting to read from invalid memory, results in "error 7", (seen from dmesg ...
5
votes
2answers
3k views

Pitfalls of SSD encryption

Encrypting an SSD is a process that is sometimes warned should be done with caution. E.g. http://en.gentoo-wiki.com/wiki/DM-Crypt_with_LUKS mentions how the SSD may keep hidden space used for wear ...
6
votes
2answers
501 views

Filling the disk with random data prior to encryption?

Filling the disk with random data prior to encrypting it will supposedly make it harder for the attacker to perform any cryptanalysis. Most sources seem to state this is because it will be harder for ...
10
votes
1answer
374 views

Slot machine segfault: what can we determine?

We walked into a casino and saw this near the entrance. I don't have a specific question, but is there anything that would be interesting to share and explain from the image?
4
votes
1answer
909 views

What tools can be use for Security Auditing for Redhat

Are there any good tools that can be used for Security auditing of Redhat Linux. That can audit all the critical areas of System and provide the detailed output of all the audited sections.
20
votes
4answers
4k views

What can an attacker do with Bluetooth and how should it be mitigated?

What are the security risks of Bluetooth and what technologies and best practices should be used to protect my device? What can an attacker do once a malicious device is paired with mine? ...
3
votes
2answers
586 views

Restarting nginx with Jenkins or Phing - is it safe to allow Jenkins to run sudo without prompt for password

I am implementing the recommendations from Integrating PHP projects with Jenkins for my own PHP projects. I have created a jenkins user in my ubuntu 12.10 server. I used Phing as my build tool and I ...
3
votes
4answers
324 views

What mechanism enforces user permissions in Unix/Linux?

One of the core pieces of security in Unix/Linux systems is limiting privileges by user. For instance, certain actions can only be done by the root user. In theory, this can keep a malicious process ...
0
votes
3answers
155 views

How to retrieve a site whose server is running Linux

I'm struggling to find a way to retrieve through Google a list of sites having Linux as their server operating system. Actually, I'd like to be able to test the following command: nmap -O ...
2
votes
2answers
182 views

Is it possible to boot into root's /bin/bash on a LUKS encrypted device?

I have to check the possibility of case mentioned in the title. An average Linux could be booted up into root's terminal directly without authentication by modifying kernel boot parameters. I'd like ...
3
votes
2answers
205 views

Safely remove an expired PGP key file

since it's possible to recover a deleted file I wonder how one can safely remove a PGP key file (with linux's command line tools) so that it's impossible to recover it. Maybe some dd command? Searched ...
2
votes
1answer
114 views

Trust linux images burned from untrusted systems

For securitys sake I'm assuming my system is successfully compromised after a targeted and/or non-targeted attack. I've downloaded some linux images and burned them to do a re-install. Since I can't ...
1
vote
1answer
86 views

How to forbid one directory only in TOMOYO (2.5)?

(For example) I want to restrict write access to /home/backup from anybody, except a particular backup script. (To protect from accidental deletion.) For this, I suppose, it is enough to have two ...
3
votes
1answer
186 views

“WICKED” entries in the default nginx vhost's logs

I have a small VPS running nginx, and for a long time now (several months, since I rented it) it has been collecting weird entries in its default (listen 80 default;) vhost's logs: 109.x.x.121 - - ...
3
votes
1answer
290 views

What are some steps to take for securing a Linux server that aren't in this list of obvious ones?

Obvious things: Disable root login (rather, don't enable it) Secure SSH (no root login, key auth only, timeout after inactivity, whitelist users who can SSH in, etc.) IP Tables firewall whitelisting ...
1
vote
3answers
179 views

Protect linux kiosk display

We use a small computer with linux attached to a big tv to display some data to the public. Normally, there is no keyboard connected. When a keyboard is connected at boot, we start the configuration ...