Securing Linux systems and applications; understanding Linux security features.

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Is cryptsetup luksFormat -y --cipher aes-xts-plain --key-size 512 /dev/sdax a insecure setup for luks [duplicate]

Is cryptsetup luksFormat -y --cipher aes-xts-plain --key-size 512 /dev/sdax insecure. If so why and what setup would be good for keeping corporate information safe?
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1answer
18 views

Linux equivalent to Windows WriteProtect key in the registry for a software based write blocker?

I unfortunately don't have access to a physical write blocker and am looking for a software based write blocker in Linux. In Windows this can be achieved by modifying the registry and setting a DWORD ...
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52 views

XCCDF check with SCE - Suse Linux Enterprise Server 11

I have written some compliance checks for Red Hat based systems with XCCDF. Some of my checks are OVAL definitions others are shell-scripts. It works great. The same checks don't work on an SLES 11 ...
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1answer
123 views

Linux responds to ARP requests for other interfaces - could this be a security vulnerability?

Linux responds to ARP requests on all interfaces by default. To explain, say you have this setup: Client 1 ---> [eth1] server [eth0] <--- Client 2 And the server's eth1 IP is 192.168.1.1 and ...
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1answer
56 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 ...
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Should I use a second/dedicated IP address for SSH?

When running a public web server (e.g., with Apache), I've heard it's recommended to bind SSH to a second IP address, different from the one Apache is listening to. But for me it seems like this is ...
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1answer
318 views

samdump2 Error reading ControlSet: _RegOpenKey

I copied both SAM and SYSTEM files from my Windows7 OS, and then used this command to read the content of the SAM file samdump2 SAM SYSTEM > mdp_chiffres.txt, but i'm getting this error Error ...
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3answers
286 views

How to (further) ensure SSH security?

I set up my Linux Ubuntu machine as an SSH server through no-ip.com and it works great. Recently I discovered the command, sudo lastb -ad -F -w which outputs a log of the most recent failed SSH ...
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102 views

Linux kernel security bugs and hardening Ubuntu? [closed]

I recently read some article about the linux kernel having vulnerabilities, I can't recall exactly where. Being new to linux, do you guys have some references on how I should prevent remote access to ...
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1answer
204 views

Pros and cons of disabling TCP timestamps

So, lynis informs me that I should unset net.ipv4.tcp_timestamps. I know that's a bad thing because an attacker could figure out which updates that require restarting the machine I haven't applied, or ...
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2answers
135 views

Secure Android app development [closed]

I'm beginning with Android App development and I want to make sure that I'm taking the proper security precautions since most apps will handle sensitive data. What security precautions should be ...
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1answer
59 views

Is it safe to host passwordless web applications/software with web GUI in Virtual Machines

I have a Linux Mint Virtual Machine which I use quite a lot with my Windows host. I have lots of Software installed there (mostly with web GUI so I can access them from host easily). So I am ...
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2answers
84 views

Protecting account ssh keys from root

How can users ssh private keys be protected from root stealing and attempting to brute force them? I cannot use selinux as the vendor will not support the app when it's in use? Thanks
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1answer
100 views

Hacked debian server alternative boot

The server of a customer has been hacked last night. It is a standard debian distribution with mysql, apache and ssh for remote access. The way it has been hacked is very peculiar. The standard URL ...
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1answer
86 views

Can a brute force attack be certainly prevented on a unix/linux shell?

I've been getting kind of curious about computer security. I know brute force has been discussed a fair bit on Stack, but I want to elaborate a bit by asking, "Is it possible to /certainly/ stop ...
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1answer
374 views

Can I decrypt a DiskCryptor-encrypted hard drive using Veracrypt?

I have a hardrive I encrypted with DiskCryptor back when I was using Windows. Now that I have Linux I want to decrypt the hard drive but it turned out DiskCryptor is not available for Linux, whereas ...
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1answer
5k views

What is real-world impact of CVE-2016-0728 (Linux Kernel Vulnerability)

Today emerged report about another serious vulnerability in opensource world, CVE-2016-0728. It is local privilege escalation in Linux kernel 3.8+. What are the the possible real-world exploitation, ...
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115 views

Security implications of android rooting

I know this question has been asked many times, but I didn't see a clear answer to it from security experts, or it is from several years ago and things might have changed. My question is double: ...
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0answers
59 views

From xss to rce in client side [closed]

I found a desktop application in Linux w/c getsvand that displays items from site xyz. xyz is vulnerable to XSS and code injected there is also executed on client side's desktop app.similar to this ...
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1answer
62 views

Blocking all incoming traffic, will it still accept a response from a request I initiated?

I am a 'newbie' when it comes to firewalls, but I am trying to launch some machines that will connect to Facebook's Graphs API. I only want these machines to contact Facebook and nothing else. By this ...
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1answer
60 views

MitM attempt resulting in ICMP redirects

I am trying to 'man in the middle' a device on my wifi network. I have configured it to use my Linux machine (also in the wifi network) as a default gateway. On the Linux (attack) host, I switched on ...
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5answers
591 views

Home Banking, antivirus safe environments OR Linux on virtual machines?

Which is the safest way to do home banking, given that I do use Windows on a tablet, I do connect to both private and public networks and I cannot use a Linux live distro right now? I've been ...
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1answer
82 views

Is there any security risk allowing regular Linux users to run arbitrary code?

I'd like to allow untrusted users to run arbitrary Node apps. If I use iptables to block everything except trusted servers, make each user's home folder only visible to them, and use runuser to start ...
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1answer
73 views

security updates for embedded firmware Tomato (router) [closed]

I installed on my Linksys router Tomato firmware. I saw and now don't understand how security updates work. It can't be that there is no vulnerability since 2010. Tomato Firmware v1.28.1816 ...
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1answer
152 views

Is BSD more secure than GNU/Linux? [closed]

BSD controls the OS while Linux is just a kernel. BSD is less popular than Linux, but which one is better in terms of security?
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1answer
74 views

IPSEC End to End Tunnel Throughput

I have established a IPSEC tunnel ( standard configuration , with ESP) , on two Linux machines (centos6 , core i7) communicating over 1 gbps LAN , and i'am checking the communication throughput. It ...
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1answer
59 views

Protect sensitive information in a password-free, shared database

I'm working on a webserver that stores resources in Redis. To make swarm-deployments as hassle-free as possible, I'm implementing an option where the server doesn't need to access the filesystem to ...
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0answers
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Practicing with return-2-libc exploits

I am trying to reproduce a return-to-libc for a simple vulnerable program. The tutorial is taken from https://sploitfun.wordpress.com/2015/05/08/bypassing-nx-bit-using-chained-return-to-libc/ I made ...
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2answers
111 views

Can malicious software be installed inside Linux swap partition?

Is it possible for a virus of any kind to be installed inside Linux swap partition? If so, could it be transferred to the system even after formatting the Linux partition only and reinstalling the OS ...
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1answer
116 views

Laptops SSD: Hardware Encryption plus DM-Crypt/Luks - Security and Performance

I just bought a new Thinkpad t450s, and put a Samsung 850 pro in it. My Cpu supports AES-NI and the SSD supports hard-ware based encryption. My question is, is there any reason to do Both ...
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1answer
162 views

What is the most secure mobile os? Ubuntu? [closed]

What's the most secure mobile os for the average day to day user concerned with protecting online banking, personal data, photos etc? And is the new Ubuntu mobile os likely to have the same security ...
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2answers
115 views

Are there any security benefits in deleting the private key of a https webserver after starting it?

Say you have a web server offering pages via HTTPS. After the process begins running, if you were to delete the private key, would this prevent private key recovery in case of server compromise? ...
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189 views

Using TPM with well-known SRK/owner passwords?

First, I will explain roughly how I plan to use the TPM: I am using something called tpm-luks which stores a key in both TPM NVRAM and adds the key to one of the LUKS keyslots. The initramfs then ...
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What is happening now with the Grub backspace key security vulnerability?

I have just read an article about a new Grub vulnerability. The article said that you can bypass the password protection by pressing backspace about twenty eight times. I am a security guy and I am ...
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Address of environment variable different for each directory

I'm writing a return-to-libc attack for a school project. My script retrieves the system(), exit() and shell addresses as follows (it's a sh script that calls some c programs): Create the environment ...
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1answer
91 views

Impact of using a NON-SSL/TLS connection for API calls on same server

I have two domains hosted on the same server, Domain A and Domain B, both domains have different IP addresses, assuming IPs 1.1.1.1 for Domain A, and 2.2.2.2 for Domain B. Each domain has a different ...
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2answers
141 views

Is using Chrome and Tor Browser at the same time secure?

I question this recently because as I was using the Tor Browser, while in the same time my Google-Chrome was opened, and I right-clicked on a word to search it in 'Disconect', when the page loaded I ...
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4answers
3k views

Can the root user be removed from a *nix system to prevent privilege-escalation?

Once a *nix system is properly configured and hardened, is it a conceivable strategy to remove all super user/root users? Are there benefits to removing root from a system altogether to prevent ...
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1answer
107 views

How to grant permission to read a text file to a specific application run by a regular user?

A text file is situated in /opt/somefolder. It contains a pair login - password read by an application when authenticating on a server. The application is run by a regular user, so that the file can ...
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59 views

How can I check whether file modified time has been spoofed on ext4?

On Debian based system (Ubuntu 14.04.3 server specifically), using ext4 filesystem. How would I discover if files have been changed, but the modified times have been made to look like the files have ...
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Under which circumstances is the default security profile of XRDP considered okay?

In xrdp.ini, the base install of xrdp on my raspberry pi*, there I have the following below. I changed crypt_level to high. [globals] bitmap_cache=yes bitmap_compression=yes port=3389 ...
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2answers
177 views

Decoding injected PHP malicious code in my server

I've found on internet similar issues, and I compared the code. This one is different. I recently found out that the CentOS LAMP webserver we use for development in our office was infected by a piece ...
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1answer
57 views

Test the security of my Linux setup [closed]

I have a Ubuntu installation running in VirtualBox. I have made a few modifications to it (some kernel modules and startup scripts) that I hope would make it very secure. Is there anyway I can test ...
2
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1answer
111 views

Linux antivirus and files bigger then 4GB

I wish to scan files that are bigger then 4GB. For example video files. I noticed many antivirus software are limited to a maximum of 4GB (ClamAV for example). So: Is there a antivirus software ...
4
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1answer
45 views

Is protecting a parent folder secure enough to protect files within that folder?

So this topic came up during a hardening exercise on Unix/Linux machines where a parent folder was marked with chmod 740 but files within that folder were marked chmod 644, and the argument went that ...
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1answer
66 views

Hydra saying cracking done and displaying random passwords

I have Hydra on my Linux machine. I want to test cracking security with Hydra on SMTP but I get no success. After about 20 messages that SMTP mechanism and a random message like [465][smtp] host: ...
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95 views

Is there a tool to detect what technologies a website uses? [closed]

I'm looking for the name of a tool I've used a long time ago, that for a given URL/website address would extract the technologies used for that site. For example that the site is running Apache, using ...
2
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1answer
190 views

Can a root user inside a Docker/LXC break the security of the whole system?

My question is probably more about the LXC than about Docker, but I wonder what are the security mechanisms to prevent a root user inside a Docker image to access the whole host. More precisely, I ...
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3answers
211 views

What should I be aware of when opening my home server to the internet?

I've built a home server (pretty much just a basic PC with a couple of big HDDs) which I would like to use as an FTP server and a minecraft server. Both would be for members of my gaming community. I ...
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1answer
131 views

Online vs offline backups [closed]

Up to this point I was using physical hard drives for backups, typically using dm_crypt as mentioned here. If online storage is used instead, and the provider cannot be trusted how much should the ...