Unix is a family of multiuser, multitasking operating system that is widely used in workstations, servers and embedded devices. The best-known Unix variant is Linux.
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2answers
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Where is my password stored on Linux? [duplicate]
Is there a specific location where the passwords are stored ?
Is it depending on which version is used ?
Are they salted ?
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1answer
35 views
Do I need logging enabled in my rules in IPFW for sshguard-ipfw to work/blacklist ip's?
From the FreeBSD handbook: "Even with the logging facility enabled, IPFW will not generate any rule logging on its own. The firewall administrator decides which rules in the ruleset will be logged, ...
2
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2answers
48 views
Does glibc2 version of the crypt function still use DES for alternative hashing methods?
I'm trying to understand how typical Linux distributions generate the password field for entries in /etc/shadow. I can't figure out what encryption algorithm is being used to produce the encrypted ...
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3answers
255 views
Are file permissions set in Unix/Linux effective in Windows or Any other OS?
Consider some files and folder in Unix/Linux OS which are configured for only read access by root, if the hard drive stolen, and used in Windows Environment, are these permissions are still effective?
...
2
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1answer
123 views
unix malicious scripts/ksh execution
I'm wondering whether my architecture poses a security risk.
Details:
The whole website is not ROOT owned but still, the APACHE user used instead has some pretty advanced permissions.
I have a ...
3
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4answers
226 views
What mechanism enforces user permissions in Unix/Linux?
One of the core pieces of security in Unix/Linux systems is limiting privileges by user. For instance, certain actions can only be done by the root user. In theory, this can keep a malicious process ...
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2answers
159 views
What's the secure way to change UNIX permissions on a harcoded file often?
I'm writing a daemon that monitors something in the OS and flips execution permissions on a file in /run/ back and forth. The file has static contents and the file name is hardcoded in the daemon. I ...
5
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2answers
220 views
How is the available entropy in /dev/random calculated (or estimated)?
It seems (to a non-expert) that /dev/random is acclaimed to be useable as a source of pure random data. However, I am curious as to the analysis of the file /dev/random.
/dev/random is a collection ...
2
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1answer
132 views
is root@localhost the same as Unix root with GUID = 0 and ID = 0?
Is a Mysql root user (root@localhost) the same as the computer root account (GUID = 0, ID = 0) ?
I mean, is it the root which is executing the script?
How can I know if the users are the same?
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0answers
288 views
Traditionnal DES scheme in Unix crypt function [closed]
In a security context course, we need to reproduce the old DES hashing scheme in the crypt program, on an old unix system.
I am actually reading the crypt page on wikipedia:
The traditional ...
7
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2answers
213 views
How a malware executes remote payload
Let's assume a malware was installed (on a UNIX-based platform) with some social engineering tricks. The original installed code itself may be benign, but the only malicious activity is that the ...
2
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5answers
496 views
Security purpose of asking admin password to mount partition on Linux
So I divided my 250GB laptop drive into 2 partitions and some swap. On the second partition which is an ext4 60GB partition I installed Fedora 17. On the other bigger NTFS partition I've got Win XP ...
2
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1answer
481 views
Is the mount manpage saying nosuid *is* secure, or is *not*?
I'm a bit confused about the description of nosuid in the mount manpage on this RedHat system I'm setting up:
nosuid Do not allow set-user-identifier or set-group-identifier bits to
take ...
4
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3answers
186 views
Could browsers improve security of stored passwords by using setuid?
On Unix-esque systems, Mozilla Firefox stores a users' preferences, web history and stored passwords in a set of files that are readible and writeable by that particular user.
This makes sense: when ...
8
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4answers
328 views
Does UNIX have a dual approval mechanism?
Sudo and logging is used to keep administrators accountable. But is there a command/configuration that lets you enforce a dual approval type control such as the the "Two Person Concept"? (eg. Two ...
2
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2answers
184 views
unix config scanner / compliance checks
I'm looking for a tool, that scans unix operating systems for configuration issues. E.g. a script that finds
PermitRootLogin yes
in the ssh config file or with other words: a script that automates ...
11
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3answers
375 views
Is passing sensitive data through the process environment secure?
Recently I have been looking for the possibility to pass sensitive information from one process to another (at process startup time) without passing it through the command line or without using a ...
1
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1answer
191 views
Installing applications with different user accounts on linux
I have basic question about installing applications on Linux operating system, using the Oracle database as an example. When installing the Oracle database package, I created a user called ora112, a ...
1
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2answers
282 views
Security issues with an append-only log in UNIX
I'm going over past exam papers for a security module I'm taking at university and there is a question which I can't give a great answer for.
As a security manager in a bank you are asked to ...
3
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1answer
2k views
what does it mean to be setuid root?
I am reading Tanenbaum's Modern Operating Systems 3e. He says "Suppose that the program being attacked [with malicious code] is SETUID root in UNIX (or has Administrator power in Windows). The ...
2
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2answers
238 views
Why superuser or administrator account should never locked?
Why should administrator or superuser account never locked regardless how many incorrect login attempts are made?
What should be done instead to alert the staff to the attempted instrusion?
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1answer
177 views
What time do dictionary attack take on salted passwords?
I was reading that the designers of UNIX password algorithm used a 12 bit salt to modify the E-table of the unix hashing function (the DES). Supposing i have a system with 2^(24) users?
Is that ever ...
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4answers
4k views
Netcat IP Spoofing
I am connecting to a server
nc -v 192.168.0.1 1111
But I want to do IP spoofing because the server on 192.168.0.1 only accepting commands from 7.7.7.7. We are two friends, I am 192.168.1.1, and my ...
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1answer
2k views
Finding environment variables with gdb, to exploit a buffer overflow
I have to exploit a very simple buffer overflow in a vulnerable C++ program for an assignment and I am not being able to find the environment variable SHELL.
I have never worked with BoF before, and ...
2
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2answers
133 views
vulnerable getlogin
I was reading "A taxonomy of Coding Errors" and I have a doubt regarding the point mentioned in C/C++ >> API Abuse >> Often Misused: Authentication(getlogin).
I fail to understand the attack vector ...
2
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1answer
198 views
Can UNIX Domain Sockets be locked by user ID?
If I created a folder /tmp/me with permissions 700, and started a process under me that starts a listen socket under /tmp/me/socket.
I currently assume that a connection to that socket originated ...
4
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2answers
724 views
What are the dangers of storing webserver temp files in the /tmp/ folder?
I have configured my first publicly accessible nginx server. I have configured it to use a /tmp/nginx folder to store temp files. This includes the body of http requests, proxy files etc. The /tmp ...
2
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1answer
106 views
What is a good method to report security breaches that are being used to actively spam?
I received an email the other day purporting to be from a bank I hadn't even heard of, so I decided to poke around. On some quick investigation, it looks like something has just latched onto some poor ...
5
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3answers
517 views
Making passwd/shadow files more secure
The passwd/shadow files in a unix-like OS contain sensitive info such as a user's password. In addition those files aren't necessarily secured: with a live CD we can access those files on the hard ...
5
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3answers
3k views
How do I ensure data encryption on Samba transmission on *NIX systems?
I have a heterogeneous system (both MS and *nix) that communicates with CIFS/SMB. How can I ensure proper data encryption at the application layer?
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1answer
524 views
Can you describe a real-life scenario of exploiting sticky bits?
Sticky bit are mentioned in every UNIX security book, but I couldn't find anyone that describes the exploitation of Sticky Bit set on a file.
Can you?
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1answer
532 views
Can Solaris' shadow hashes be created by better algorithms than the default DES-based hash?
By default, Solaris uses Traditional DES to encrypt password hashes in the shadow file.
Is there a way to harden the security by changing this default behaviour and make it to be hashed using a ...
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3answers
308 views
Security Implications of setting passwd as suid
When the passwd command is executed, it runs as the root user. Can't this be exploited? If not, why?
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3answers
140 views
Is it safe to attach a potentially malicious hard drive to a Solaris machine?
We bring in hard drives from un-trusted sources and would like to ensure that they will not contain any harmful content.
What kind of risk is there for Solaris? As in, if Solaris is running, and I ...
1
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2answers
358 views
Sun ILOM / Out of band management security concerns
I would like to get some outside opinion on this if possible, although I do not know what to ask.
Sun ILOM is an Out-of-band management system. I understand it is a separate OS on the box that is ...
10
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3answers
386 views
Is it insecure to have an SSH server on a workstation?
I know one systems administrator who runs SSH Server on his workstation to push files to it and check things from a phone but I think it is a bad idea for several reasons:
An operations workstation ...
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3answers
589 views
Why are people saying that X-windows is not secure?
Why are people saying that X is not secure?
With X I mean: https://secure.wikimedia.org/wikipedia/en/wiki/X_Window_System
p.s.: The OpenBSD team succeeded with priviledge separation in 2003, WHY ...
2
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1answer
150 views
OBSD X11 as non-root?
If running X11 as root is not a very good idea, then can anyone mention a method/solution, how to still use a GUI, and not having X11 as root?
3
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1answer
217 views
OpenBSD-based LiveCD / LiveDVD - is it secure? is it offical?
http://jggimi.homeip.net/livecd/downloads.html
Does it get deeply audited like the original OpenBSD?
Is it an offical "port"?
Experiences with it?
Thank you!
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4answers
3k views
OpenBSD vs. NetBSD security
If i search for the two words: OpenBSD and NetBSD on:
http://www.exploit-db.com/
then i get 17 hits regarding security bugs on OpenBSD, and 8 hits regarding security bugs on NetBSD.
So what are ...
8
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1answer
164 views
What is your default umask set to?
What is your default umask set to? Did you run into any problem setting a stricter default umask?
7
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3answers
465 views
What prevents this exploit from working (unix SUID)?
If I have a user on a unix system where Im allowed to create new files, what prevents me from downloading an executable file onto that system which is already SUID'ed to root on a different system?
...
10
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7answers
347 views
UNIX Servers: Possible intrusions or attacks that do not use any of the open listen sockets
What type of attacks are there that do not use open TCP or open UDP ports?
Is it safe to assume that no open ports means no remote access?
(Excluding the possibility that there is a badware already ...
5
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2answers
142 views
How is the password prompt going to protect me from ruining my computer?
On Unix based systems, I'm often prompted to enter my password before installing or running a program.
Why does this protect me?
If I'm running a kiosk, I understand that a password might prevent ...
