Securing Linux systems and applications; understanding Linux security features.

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1answer
93 views

Honeypot used as as a proxy?

I'm running Kali Linux on my system at home to practice pentesting. If I implement a honeypot on my system could it be possible to use that as some sort of proxy server? I was thinking it wouldn't be ...
15
votes
8answers
4k views

Why is it possible for the root user to delete the logs?

I always thought the greatest benefit of the logs is to confirm to you that your machine has been hacked. However I see hackers bragging about "rooting" servers all over the Internet. Whats stopping a ...
2
votes
1answer
80 views

Give only execute permissions to a Linux binary (prevent inspection)?

I'm writing an assignment for a security course, and I'm trying to create an executable which students can interact with (ie, execute), but not inspect. In particular what I'd like is for them to be ...
1
vote
2answers
249 views

Validating security log configuration (rsyslog and syslog-ng) for PCI DSS 10.5

I work for a Level 1 merchant with annual onsite QSA audits, so this is a huge deal. PCI DSS 10.5 requires the entity under test to "Secure audit trails so they cannot be altered". In our Unix and ...
2
votes
1answer
48 views

Running rkhunter on Linux

Currently each time before an application and after an application is either installed or updated including regular patches, the command rkhunter --propupd is run, followed by the command rkhunter ...
1
vote
1answer
70 views

Debian 8 and few questions about Graphical Firewall?

I have installed Debian 8 today, and so far so good. What I want to achieve now is to install firewall but can't find Firestarter in repos (discontinued ?). So, I have installed a GUFW and set it up. ...
2
votes
3answers
121 views

Linux File Security when connected to internet [closed]

Let me first admit that I am a nobody in computer security - I just know the various threats generally known to public. I have a Linux Cent OS 7 installed on my computer which is connected to the ...
6
votes
2answers
289 views

Does the new Fedora package manager allow unauthorized installations?

I just upgraded to Fedora 22. The biggest change from the previous version is that the yum package manager is now replaced with dnf. One change I've noticed is that if you try to execute a command ...
11
votes
3answers
4k views

Are there ransomware infections of Ubuntu Linux in the wild?

Due to the recent media coverage of ransomware attacks several people for whom I've provided personal computer support in the past have expressed concerned. The majority of these people are running ...
5
votes
2answers
331 views

How to secure a local socket?

I have made a service written in c that runs on the Android operating system as a core service. I have a few Android apps which communicate with this service via a socket connection (Java -> C). My ...
-4
votes
3answers
542 views

How to capture the traffic of a computer in my LAN?

I have a machine with the Windows 10 preview installed and I want to capture all the traffic it sends for a day and then block all the MS hosts it sent data to without my direct permission. I don't ...
6
votes
3answers
1k views

How to securely read a physical memory address in Linux?

I am trying to read a physical memory address in a device running embedded Linux with our application. The widely suggested method is to use mmap, convert it into virtual address and then read the ...
1
vote
1answer
100 views

Automate certificate signing in Linux

In a private network I wish to automate signing for new clients/servers. Something like this: New client is created (dockers & etc) The client create a new private key and a CSR The client send ...
2
votes
1answer
78 views

Run fuzzer on any service or process in Linux

I have seen examples of fuzzers to submit different inputs to some application or port. How can we run fuzzers on services or processes like any background process for any application? Any ideas or ...
3
votes
1answer
132 views

Do major linux distributions differ with regard to releasing security patches? [closed]

For a non-commercial user, is there any difference between major distributions regarding the time needed for security patches to be available? Does the "enough eyeballs effect" takes places in this ...
4
votes
1answer
103 views

RSA fingerprint automatic change or have I been hacked?

today I tried to connect to my Digital Ocean VPS through Putty(kitty) as usual, but I got the message that the server's cached fingerprint had changed, and that it could be a security compromise. I ...
-1
votes
1answer
44 views

SSLStrip with autologin [closed]

What can I do to sniff the traffic by SSLStrip when the user has automatic login to the site?
1
vote
2answers
145 views

What are some Linux commands for genrating and verifying digital signatures?

I am attempting a workflow to exemplify the process of digital signature using asymmetric cryptography. If I understand correctly then the public key and the private key in an asymmetric ...
1
vote
1answer
47 views

What is the risk of data being recovered from SAN storage after logical deletion?

The specific scenario involves Linux servers on VMware hosts with SAN storage. If files containing sensitive data are deleted by Linux, can they be recovered by a low level tool similar to what might ...
1
vote
0answers
51 views

What is the security value of chattr +s?

Most modern Linux file systems support extended attributes. +s is secure deletion which ensures (at least intends) that the data in a file is overwritten with zeros when the file is deleted. Some ...
2
votes
0answers
51 views

Wayland Partial Encryption for Mouse / Keyboard? (Also X and RDP)

Question What are the best practices for implementing Partial Encryption, to encrypt just the input devices (mouse/keyboard, etc), not the actual video display, during remote desktop sessions using ...
2
votes
1answer
454 views

Man in the middle attack, bridging wlan interface to virtual wired interface at0

I'm trying to execute a Man in the Middle attack on my mobile phone, I have two wireless cards, one inbuilt in the laptop, running AR9285 atheros drivers, the 2nd is an Alfa AWUS036NHA card with an ...
11
votes
3answers
1k views

What security measures should be taken when running a Linux web server out of our office?

I am interested in running our company's web server from our local office. The office makes use of file sharing and NAS devices among other common office protocols. The worst case scenarios I've ...
13
votes
3answers
2k views

Breaching security of a notebook with full disc encryption when screen is locked

I am using full disc encryption on my portable computer (running Ubuntu). The setup requires me to enter a password during the boot sequence to access fully encrypted hard drive. There is no ...
2
votes
2answers
99 views

Prevent Plain-Text Passwords Output by a Script From Being Accessible in the Future

Let's say I have a Bash script that generates a password, creates a new user with that password, and then tells me what the password is: # Generate a password and set it to $PASSWORD PASSWORD=$(tr ...
6
votes
1answer
402 views

Are encryption keys wiped from RAM before hibernate, or how to do it (Luks and Truecrypt)

Using Linux, I have system and swap/hibernation partitions encrypted with LUKS, and data partitions encrypted with Truecrypt, and I am wondering when I put my laptop to hibernation if the encryption ...
4
votes
1answer
139 views

LUKS TPM disk encryption attacks

Is it possible, or are there any known attacks, to get the encryption key for disk encryption tpm-luks? (Linux LUKS using encryption key stored in TPM) I know that there are attacks like cold boot ...
-4
votes
1answer
125 views

Hacking into a simple linux server [closed]

I'm very new to hacking in general so I wanted to learn more. I have an exercise, whereby we have a raspberry pi with a simple website on it and we have to get a file and the stored gpg private key on ...
1
vote
2answers
146 views

Will a wildcard SSL work properly for an A record subdomain pointing to another domain/website?

Client has wildcard SSL for his domain/subdomains. The application we are building is on one of our linux servers using one of our IP addresses and is contained within an account named ...
0
votes
1answer
114 views
4
votes
4answers
178 views

Should I format storage after buying it?

I've just bought a new (unused) external HDD. Should I format it or is it save to use it directly? Did it already happen that a device was infected before the first customer use? Will formatting ...
0
votes
2answers
73 views

Testing shellshock with PHP

I have been trying to test shellshock vulnerability on PHP similar to this answer. I am running Apache server with PHP running as mod_php. The PHP version is 5.3.10. I have a phpfile (phptest.php): ...
2
votes
1answer
265 views

Security research on Operating system security measures, where to start?

I am researching on operating system security, And I don't know where to look for more information on this. I could find the following sources, but I need more guidance. Sources: Microkernel ...
2
votes
1answer
70 views

Properly solving IP leaking from WebRTC and other apps with STUN when using a VPN

This is really a follow-up question from this: Stun scripts/webRTC IP leaks I'm connecting to a VPN using a virtual adapter, which has a default routing rule so all traffic goes through it. I still ...
1
vote
0answers
193 views

Converting Metasploit module to standalone Python script [closed]

How easy is to convert Ruby code to Python code and to change Metasploit module into standalone Python script for Linux?
1
vote
1answer
92 views

Is it possible to disable `ypcat passwd`

We have an old NIS setup which, at geological speed, is being replaced by a Kerberos one. In the meantime, all the (non-root) users can simply type ypcat passwd and get the hashes of all the users' ...
5
votes
1answer
2k views

How are shopkeepers getting the MAC address of wifi enabled smartphones?

It is clear that some big malls are tracking all the wifi-enabled mobile phones before they are connected to the network... How can this be done? I have a similar issue... how to get the MAC address ...
1
vote
2answers
122 views

$chsh command security with Set-UID

Why does $chsh have to be a Set-UID command? What are the vulnerabilities of a normal user changing his/her own shell from perhaps bash to zsh? Any help would be greatly appreciated!
9
votes
3answers
5k views

How to pass PCI DSS 2.0 anti-virus requirement (5.1) on Linux?

PCI DSS 2.0 Requirement 5.1 states: 5.1 Deploy anti-virus software on all systems commonly affected by malicious software (particularly personal computers and servers). This requirement ...
-1
votes
2answers
58 views

Prevent fake gateway device attached to PC's network card

Office. Several PCs with Linux. Internet is limited on gateway level, so nobody could do POST-requests over HTTP. We prepared several measures to prevent data leakage on infrastructure level, but ...
1
vote
1answer
90 views

Strange entry in Apache's ports.conf

I am not sure if this may indicate a compromised server or if I'm just being paranoid. While fiddling around with Apache and Webmin on a new Ubuntu 14.04 virtual server (as well as DNS records for ...
5
votes
1answer
154 views

Automatically enumerate missing patches on penetration test

Nessus, when running a credentialed scan can check patch levels and return vulnerabilities when a package is one that hasn't been updated to the latest, non-vulnerable version. What is a good way of ...
4
votes
3answers
75 views

How risky is to use non-free wireless network driver?

Intel wireless network adapter in my computer requires a non-free driver to work. I don't want to install non-free software to my debian system. However it is a notebook and without wireless network ...
2
votes
0answers
37 views

Is an unprivileged LXC where the host user itself is mapped to 0 less secure of one where one of its subids is mapped to 0, and why?

Instead of creating "common" LXC unprivileged containers where all the users are mapped to (unprivileged) subuid/gid of my host user, I'm considering a mapping where my host user itself will be mapped ...
61
votes
3answers
109k views

What is the difference between authorized_key and known_host file for SSH?

I am learning basics of SSH protocol. I am confused between the contents of the following 2 files: ~/.ssh/authorized_keys: Holds a list of authorized public keys for servers. When the client ...
1
vote
0answers
31 views

iptable ip_conntrack_max testing

I was trying to understand how ip_conntrack_max works so i have created two VM and set ip_conntrack_max to 10000 I used hping to open 10000 udp connection on VM using following command hping --udp ...
2
votes
2answers
93 views

Vulnerability test for CVE-2014-2483?

I am in penetration testing on a server with Linux RHEL6/7 os. Vulnerability databases such as http://www.cvedetails.com/ mentioned the vulnerability CVE-2014-2483 for Java in Linux RHEL systems. I ...
4
votes
3answers
213 views

How to choose a linux for learning? [closed]

I am beginner in Security. My first assignment is about "Linux firewall using IPTABLES" . I know about Ubuntu, backtrack and kali Linux. How to choose a Linux distribution to learn about security?
1
vote
1answer
231 views

Cannot connect using ECDH-RSA-AES256-SHA

I try to establish an SSL connection using the ECDH-RSA-AES256-SHA cipher using OpenSSL, but it fails saying "no shared cipher": On the server, I run: $ openssl s_server -cert selfsigned_cert.pem ...
-8
votes
3answers
2k views

Why are people saying that X-windows is not secure?

Why are people saying that X is not secure? By X I mean: https://secure.wikimedia.org/wikipedia/en/wiki/X_Window_System The OpenBSD team succeeded with privilege separation in 2003; why didn't the ...