Securing Linux systems and applications; understanding Linux security features.
2
votes
1answer
33 views
Ideas on how I can fragment captured network traffic?
I am trying to create a lab environment where I can analyze common IDS solutions (starting with Snort specifically) and their ability to reassemble fragmented IP trains. I have a collection of ...
4
votes
1answer
17 views
What security problems does copying .Xauthority to another user present?
If I want to use a GUI application with another user (example: webbrowser), I can copy the .Xauthority file to that given user's home then I can "su - user" and start the GUI app.
Question: but what ...
0
votes
0answers
2 views
Prevent children of process protected by seccomp from having same seccomp protections? [migrated]
I'm writing an application which is protected by seccomp.
This application uses fork() and then execvp() to run certain programs.
It seems as though any child process of my program will be constrained ...
-6
votes
0answers
55 views
is linux NSA-free? [on hold]
Does Linux have backdoors for 3-letter agency? or 3-letter agencys have to hack to access a computer running linux?
I asked it, beacuse i believe close-source programs etc. windows, osx has nsa ...
-1
votes
0answers
12 views
VA Scan for Linux server Running with Apache and SQL [on hold]
I want to do VA for Ubuntu server installed with Apache and SQL.
Which open source tool you recommend?
-1
votes
0answers
25 views
How to identify the script that's sending spam from my server? [on hold]
So, this is what I wanna know. How do I identify the script that is sending spam from my server?. Server is using exim. Maldet scanning did not help much. Any advises ?
-2
votes
0answers
65 views
Am I a victim of industrial espionage? [closed]
I had a weird experience, that I don't quite know how to explain.
My setup is this:
I have my desktop machine, which I connect to my company's VPN. On this machine I also run a VirtualBox VM with ...
0
votes
0answers
21 views
What else can we now do with the new GCC5 to improve codebase hardening [on hold]
Noting the recent question: What is the most hardened set of options for GCC compiling C/C++?
Is there anything else that can be shared regarding the new version of GCC, v5 for 32/64bit targets.
I'd ...
3
votes
0answers
21 views
How do I request a certificate from CEP / CES on a Microsoft CA on OSX or Linux? [migrated]
This article describes how to request a certificate from AD CS (Active Directory Certificate Services) from a non-domain joined windows computer.
I would think the same principals apply to non ...
0
votes
0answers
23 views
Threats faced by IPC in multi user system [closed]
I am learning about IPC in Linux. I see that Linux is a multi user system and the programs I start run with my privilege (so programs run with logged in user's privileges - euid). But different user's ...
2
votes
2answers
70 views
What are the security risks in leaving 'sudo' inside my production code?
I have a script that can only run successfully with root permissions
But in development it's really hard to run with root permissions (in my development environment) so I add 'sudo' when ever it's ...
0
votes
1answer
44 views
php- is my code secured enough to protect from remote command execution when using shell_exec()?
I am using shell_exec function on the following variables to execute commands on the shell:
fname (characters only)
fpack(characters only)
email (a valid email address)
My code is:
<?php
...
3
votes
1answer
74 views
Linux/ssh - Forensic question
In a Linux terminal, I made a ssh connection from A to B and I used commands to read some files stored in B. Then I disconnected and I closed the terminal.
Is it possible to find on A, informations ...
1
vote
2answers
43 views
How to change default cipher in GnuPG on both Linux and Windows?
How can I change the default symmetric cipher used by GnuPG from CAST5 to another?
I'm using GPG4Win on Windows, but would also be interested in a solution for Linux.
-4
votes
3answers
107 views
Can I do hacking using Windows OS? [closed]
I have searched the web a numerous times but haven't found an explicit answer to my question.
I've studied (at school and on my own) computer networks for 2 years, doing active programming for 4 years ...
1
vote
2answers
74 views
How to test the php vulnerability CVE-2014-3515
How to test if I'm vulnerable regarding CVE-2014-3515? My vendor supplied me with a patch and verified that it installed however I would like to verify that I am no longer vulnerable. My vendor ...
5
votes
2answers
87 views
Four eyes authentication for command execution on Linux. (OS level) [closed]
I reached the end of the internet with no success, so now I turn to you guys.
What I'm after is a way to implement four eyes principle on the OS level for certain commands in Linux.
Example :
The ...
1
vote
0answers
55 views
open ports on a netgear N-150 router; disable SPI firewall? [closed]
How do I open all ports? At least internally, for LAN traffic from 192.168.1.x to 192.168.1.x I want all ports open. Even if it creates a security problem.
thufir@doge:~$
thufir@doge:~$ nmap -p ...
0
votes
0answers
35 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 ...
1
vote
1answer
46 views
Snort even though working properly does not report majority of rules
I have installed Snort 2.9.7.0 and it does not detect majority of attacks, such as nmap port scans, downloading exe files, opening documents containing keyword "root".
I use Snort together with ...
1
vote
2answers
110 views
Roommate Frequently Hacked — How Do I Protect My Network/Devices?
If you absolutely had to share a network with a user who had a very lax approach to security and was frequently hacked (1-2x month for over a year now), what might you consider doing to secure your ...
2
votes
0answers
12 views
Anomaly - avconv tool getting corrupted randomly [migrated]
I am facing a strange problem with avconv which is a tool for processing videos part of libav-tools package.
I am on a local ubuntu server 14.04.1 LTS.
What happens is that the avconv tool is ...
1
vote
1answer
29 views
Can sshd block IPs with failed attempts or is a tool like denyhosts or fail2ban necessary?
I am only indirectly familiar with denyhosts (and only just discovered fail2ban) and they certainly seem like worthwhile tools. However, after looking through the options for sshd_config I am trying ...
4
votes
1answer
95 views
Explain the last part of how Mitnick hacked Tsutomu Shimomura with an IP sequence attack
I was reading up on why TCP ISNs need to be randomized, which led me to this write up by Tsutomu Shimomura. I understood how IP address spoofing and predicting the ISN helped the attacker establish a ...
0
votes
0answers
27 views
Improve the security of a website implementing the least privilege principle [duplicate]
I am a beginner and I am trying to program a secure website to improve my skills and knowledge. I am under Linux and I am using LAMP with php. My website is similar to a social network so people will ...
0
votes
0answers
87 views
Improve the security of a website implementing the least privilege principle
I am a beginner and I am trying to program a secure website to improve my skills and knowledge. I am under Linux and I am using LAMP with php. My website is similar to a social network so people will ...
3
votes
1answer
140 views
My sendmail started sending spam; what is causing it to do so? [closed]
Today my sendmail service started sending e-mail to various addresses.
/var/spool/mail:
From MAILER-DAEMON@noxcommunity.com Fri Jan 30 22:15:30 2015
Return-Path: ...
1
vote
1answer
83 views
Security of LXC compared to OpenVZ
For years, I'm now using OpenVZ on my server, but support discontinued for Debian and Ubuntu, current releases seem to focus on LXC now, which is not a bad idea from the point of comfort.
But what ...
1
vote
2answers
159 views
How should I deal with adware in chrome on ubuntu?
I use chrome (but also have firefox) on ubuntu 14.04 32-bit. Recently I started getting popups from 'softwareupdaterlp.com'. I had the sense to realize it was not legitimate and I didn't click install ...
9
votes
1answer
995 views
Is Java vulnerable to glibc GHOST Vulnerability in Linux?
I see on our RedHat Linux platform that "java" process has dependency over glibc library:
[root@hpproliant1 ~]# ldd /usr/bin/java
linux-gate.so.1 => (0xffffe000)
libpthread.so.0 => ...
1
vote
1answer
65 views
OpenSSH downgrade attack
I have tried to implement a downgrade attack against the SSH protocol as the first steps (encryption protocols exchange) are not signed, as per RFC4253.
The idea is to intercept (mitm) these steps and ...
0
votes
1answer
48 views
Bogus HostName Causing Suspicion of Man In The Middle
I have servers on a LAN reporting my laptop with a bogus hostname. This is making me suspect a man in the middle attack.
Here are some details:
From an Ubuntu Linux 14.04 laptop, I logged into an ...
0
votes
0answers
92 views
Is there any method to prevent/trace ddos attack?
I have a debian linux server which run a few online game services. I have some competitors in this area and i think one of them is behind the ddos attacks.
I have full access to the router, so I set ...
2
votes
2answers
56 views
Linux Repo Security
Can a registered 3rd party repo spoof critical packages (e.g libc6) and have them installed on apt 'upgrade' operations?
What are the best ways (configuration) to help manage 3rd party repos to ...
4
votes
2answers
94 views
Is there a way to check for “hollow” processes, or malware hidden within “normal” processes
I recently came across an article on the The Verge, which centers around the concept of commercial malware production and how it's used around the world. The article introduced me to a number of ...
2
votes
1answer
57 views
How does the Samba misconfigured '/etc/passwd' file security bypass vulnerability work?
I just found this vulnerability on http://www.securityfocus.com/bid/36363/references, which affects several samba server 3.0.xx.
Can anyone explain more about this vulnerability? How this bypass ...
1
vote
2answers
86 views
About SHA1 in default Disk Encryption in Linux
Link to the Thread:
Recommended options for LUKS (cryptsetup)
I wonder what's the exact difference between SHA1 and SHA512. I know that SHA512 has a longer key but I've read that it doesn't matter ...
0
votes
0answers
28 views
Bruteforce with Hydra [duplicate]
I'm trying to use a Hydra script in the following scenario on localhost and Linux:
After web form login, my app redirects to another page with header(Location: internalpage.php)
I use this syntax ...
5
votes
2answers
545 views
Security of Linux Full Disk Encryption (Ubuntu / Mint) -insecure?
I'm wondering, why is Ubuntu and Mint using SHA1 for Full Disk Encryption? I heard several times that SHA1 shouldn't be used anymore because it is weak and it could be cracked.
Could you guys ...
2
votes
1answer
71 views
Upload a file into directory with public write access
I know it is not right to set a permission for the folder as 777, but if it is done so will it be possible to upload a file into that directory without ftp access ?
Here is what I mean
Lets say the ...
3
votes
1answer
74 views
Key generation: Differences between GnuPG classic, stable, modern?
I plan to create a 4096 bit RSA&RSA key pair:
gpg --gen-key --personal-digest-preferences SHA512 --cert-digest-algo SHA512
Is there any difference in generated key quality between versions 1.4 ...
0
votes
0answers
57 views
Is there any security risk with adding a **root's** public key to the local user's authorized_keys (so root to login as a user non-interactively?)
Background:
I want to try unprivileged lxc containers a try on my small web server (hosting 2-4 users). Since the server is shared among friends, we decided to separate our services from the machine ...
3
votes
2answers
100 views
Firewall egress filtering / quick whitelisting
Suppose your Aunt or Uncle is easily fooled by phishing attempts and their computer has multiple root kits and key loggers running. Assume their computing habits will never change.
Looking at his ...
0
votes
0answers
85 views
Protecting against bad USB in ubuntu
I am referring to this thread:
How to prevent BadUSB attacks on linux desktop
Since i want to install ubunto onto a possible infected usbDrive using a live DVD and the installation manager i was ...
0
votes
2answers
93 views
Running tails on a corporate computer
Is it safe to run TAILS on a corporate computer?
I mean a corporate computer that has hardware cryptography and probably some backdoors; and, by safe, I mean that nobody will be able to recover what ...
0
votes
1answer
23 views
SELinux ignoring /etc/sysconfig/selinux directive
I'm running SELinux on CentOS 6.5. In /etc/sysconfig/selinux I have set SELINUX=permissive. But everytime the system starts, sudo getenforce shows SELinux as Enforcing. What could be causing it to go ...
3
votes
2answers
70 views
How to securely install software on Ubuntu?
How to install a software like Sublime Text on Ubuntu 14.04 LTS and mitigate against a MITM attack? There is a PPA available, but the PPA must be added manually.
I don't see any PGP keys or MD5 ...
7
votes
2answers
167 views
List all files with only arbitrary file path read, but no directory listing nor sudo
I have found a path traversal vulnerability that allows me to read any path on the server that does not require sudo.
To fully exploit this, I would like to know which files exist in each directory ...
-1
votes
1answer
172 views
ARP: Forwarding or dropping with IPTABLES
So, I ve been trying to ARP Poison my home computer and router (Intended to learn and discover the networks bahaviour). And with success. The whole time I ve been using:
with ...
0
votes
0answers
65 views
Secure password transfer from stdout to another window
I am currently trying to build a little, secure password manager. As of now, I've implemented the encryption. Each website has its own file and each file has a number of fields (Most commonly username ...
