Securing Linux systems and applications; understanding Linux security features.

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3
votes
1answer
46 views

Prevent snapshots of VPS

Pretend I have a server. Is there anyway to prevent (or make more difficult) the administrator from taking snapshots? Feel free to give me a software way, or suggest if I should change server types; ...
1
vote
1answer
113 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 ...
1
vote
2answers
102 views

Ettercap Remote Poisoning

I have a question about one parameter and that's it. When I'm doing DNS spoofing I have to use arp:remote. Can someone explain to me what arp:remote means? I read the man page, but did not ...
1
vote
1answer
112 views

Yersinia raw packet

I'm using Yersinia to pentest my network. There are two options send raw packet and creating DHCP rogue server I don't understand fully. Can someone explain the meaning of these options?
3
votes
1answer
147 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 ...
-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?
4
votes
1answer
113 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 ...
5
votes
2answers
258 views

Can CVE-2015-7704 - ntpd kiss-of-death affect NTP time servers or just clients?

As the ntp.conf file on a linux server can be setup to allow the system to act as both a client to the public servers and a time server source for local systems am I correct in assuming that it (the "...
4
votes
1answer
143 views

Mitm attack problem [closed]

I have a problem with implementing this attack. I have a kali linux machine on vmware workstation. My router is - 192.168.1.1 My victim ip is - 192.168.1.254 arpspoof -i eth0 -t 192.168.1.1 192.168....
1
vote
2answers
192 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 ...
2
votes
0answers
53 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 ...
5
votes
2answers
373 views

Decrypting SSL using Wireshark on Linux vs Windows

I'm working on decrypting my own traffic that gets sent through Wireshark and I've been following this guide for reference. I have been using the SSLKEYLOGFILE environment variable and I can get the ...
2
votes
0answers
52 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 X,...
1
vote
1answer
49 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 ...
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
113 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 -...
4
votes
1answer
167 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
144 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 ...
0
votes
1answer
149 views

How to detect arp spoofing using iptable? [closed]

How can I set iptables to detect arp spoofing on linux?
1
vote
2answers
195 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 www.somedomain....
4
votes
4answers
181 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 ...
2
votes
1answer
74 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
251 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
103 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' ...
0
votes
2answers
75 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): &...
1
vote
2answers
169 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!
-1
votes
1answer
106 views

Understanding HTTP response from Linux Server

I am working through a question that involves someone using a vulnerability in a Linux server in order to gain access to it. The first part of the question states In monitoring the network activity ...
-1
votes
2answers
62 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 ...
7
votes
2answers
339 views

Prevent ARP spoofing with dynamic static entry on Linux

ARP spoofing detection/prevention seems to be quite popular here. With other techniques like port stealing aside, I'm wondering if the following could work to prevent it: Whenever my Linux ...
5
votes
1answer
202 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 ...
1
vote
1answer
109 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 ...
4
votes
3answers
77 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 ...
8
votes
5answers
2k views

I don't recognise my DNS server's address: does this mean I am compromised?

I'm using the Ubuntu GNOME Linux distribution as my desktop. Recently, it became impossible for me to connect to the Internet with it. When I checked its network settings, I saw that the DNS address ...
1
vote
0answers
33 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 -...
1
vote
3answers
571 views

TSource Engine Query DDoS attack

My gaming machine is under DDoS attack and when I used Wireshark I found the following string "TSource Engine Query" in all UDP packets coming from random IP's. I found using Google that some gaming ...
4
votes
3answers
238 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
360 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 -...
2
votes
1answer
276 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 ...
5
votes
1answer
185 views

My dlink router seems to be compromised

By chance I read today about this huge vulnerability regarding my router Dlink DIR-600. ( http://www.s3cur1ty.de/m1adv2013-003 ) Just out of curiosity about what I would find, I tried to send some ...
4
votes
2answers
878 views

Malware (adware?) infection on linux

Recently I've get stuck with a malware(adware/virus ?) which I can't remove. here is the condition: I'm using Linux (Archlinux), it's uptodate and I don't install any packages outside standard repos ...
1
vote
1answer
44 views

Sensitive information to exclude from Linux server before providing complete backup to vendor for troubleshooting [closed]

A vendor requested a complete backup of a server for troubleshooting a bare metal restore issue, but they said we are free to exclude any sensitive data. I’m thinking I’ll exclude: /etc/shadow exim....
-1
votes
1answer
514 views

SQLMAP --OS-SHELL error [closed]

root@kali:~# sqlmap -u http://www.a***********.com/info.php?id=2 --os-shell _ _ _| |_____ _ {1.0-dev-nongit-20150907} | -| . | | | .'| . | || |||||,| | || |_| http:/...
8
votes
7answers
335 views

is it possible to keep something invisible to the server admin?

Let's considering the following scenario, an investment firm runs a computer cluster(using red hat as os), some computation which involves some company's trading secret will run on it, there is a SA ...
3
votes
2answers
416 views

Does CVE-2015-5352 work if there is no active X-Server?

My security program shows that one of my servers is vulnerable to CVE-2015-5352. If X-Server is not running (not even installed) is the system really penetrable by that vulnerability?
-4
votes
3answers
108 views

Reverse Engineer and Exploits researching [closed]

Can some one give me a start point for finding exploits in software and reverse engineering? I need some kind of a book or a site... I have background with programming with high and low level such ...
1
vote
2answers
107 views

Public Key Pinning and subdomains

Shortly I have intend to install new webserver and I'd like to secure users a little bit more. I already have domain, (virtual) server and everything else that matters when configuring a server. ...
-2
votes
2answers
286 views

Use of Nmap ssl/http md5 and SHA1 hashes

I have below stated result on of the system by map: 443/tcp open ssl/http Apache httpd 2.0.52 ((CentOS)) | http-methods: GET HEAD POST OPTIONS TRACE | Potentially risky methods: TRACE |_See ...
4
votes
2answers
88 views

Is it a good practice to use certificates as a mean of client identification in a cloud environment

My software system is running a cloud infrastructure where having Linux machines VPN into OpenVPN gateway is a setup requirement. Also, there may be cases when software on the aforementioned Linux ...