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Does anyone have a general step by step list on how to try discover rootkits on a Linux or Solaris server?
I'm looking for to to manually find the rootkit, not by automated software.
For example:
Places to look for suspicious files?
Search commands to pick up weird file behavior?
Weird looking traffic picked up from s... |
Does anyone have any suggestions on securing an Android device? I'm not particularly interested in enterprise level software - I'm looking to secure my own ZTE Blade phone which has a lot of personal information on it.
Question taken from: http://www.reddit.com/r/netsec/comments/hsdgc/best_practices_for_securing_an_and... |
I got shot down on ServerFault recently for suggesting that SSO can be less secure than having different credentials for each service. What are the arguments against SSO?
|
i'm interested in software or set of scripts to keep a lists of filtered IP that attempt to brute-force ssh, and to label an IP as brute-forcing i would add some checks like:
one attempt to log as root is a ban
three attempts to log as a nonexistent user in a day is a ban
a port scan is a ban (this i know there are to... |
If you where called by Sony right now, had 100% control over security, what would you do in the first 24-hours?
|
I have a web server. I recently received a large volume of web traffics, after tracking it down, it is coming over a commercial VPN provider. Is there any way to keep the tracing going, beyond the VPN?
|
Let's say I want to set up a sandbox or playground in PHP that users can use to create (or paste in) XML and XSLT, then transform the XML via the XSLT (by means of PHP 5's DOMDocument and related objects).
So, in a simple example, we'd have a form with two textareas - one for XML and one for XSLT. The user would enter ... |
We are in need of an encryption process for backups of very valuable data. This data will be stored on a distributed filesystem, so even with permissions set right, it's not out of reach that this data is copied or read. I'm searching for a reasonably simple method to encrypt tar archives and only have them readable by... |
As part of a large organization looking to implement VoIP, to get on the bandwagon of savings and converged network focus, I'm being asked to look at the security concerns to develop a policy to help define a direction.
Since I'm a geek first, and a security person second I started immediately down the road of "What ... |
I'm wondering if there is a web application firewall (WAF) equivalent of VirusTotal? A site where I can throw for example injection strings, exploits or xss, and it will tell me what the default setups for different WAFs will detect.
I know there is the ModSecurity site out there which I could set up myself and experim... |
How would you go about securing the online identity(ies) of someone as best you can after they've died, when they haven't put anything in place ahead of time for this event?
Assume we don't know how many identities or services they've used, but at the very least includes 3 email accounts with different providers, and ... |
In the context of online accounts and identities, what are some best practices to prepare for the one certainty we all face: not a one of us will get out alive.
|
What are the benefits of someone building a private Tor network? ...One that is disconnected from the well-known network being used on the Internet at-large.
My intent is to make Tor more corporate-friendly so that it:
Prevents nodes from being operated by untrusted/hostile parties (exit node eavesdropping)
Prevent... |
I have a HP 6510b notebook.
Are there any solutions for hardware encryption? I mean I don't want to use software encryption like LUKS, but I don't want that that if my notebook gets stolen the thiefs could get my data stored on it.
Are there any methods, e.g.: a password prompt shows up when I want to boot my pc (eve... |
E.g.: Can I make a better full disc encryption with e.g.: LUKS using the TPM? How?
|
So if I use e.g.: LUKS, and I always suspend my notebook, then are there any methods to modify the unencrypted /boot? It contains the kernel!
Or if someone tries (evil maid) to modify the /boot then he has to power off my machine, but later I will notice that! Are there any backdoors of this concept?
|
Generally denying login attempts after X amounts of incorrect attempts for Y amount of tries is a very basic way to prevent bruteforce attempts or malicious login attempts.
Yet, surely doing this is meaningless if you allow successful login with the correct password? In which case getting an error or a warning message ... |
On Windows Server 2008 R2 operating as a standard user, when I open Task Manager I can see all the processes from different users on the system. I have the option to click "Show all processes" which requires elevation, which does indeed show all processes.
Why though can I see processes from other users (Including othe... |
As I understand WiFi with a PSK, such as WPA(2)-PSK or WEP, anyone on the same network can decrypt anyone elses packets because everybody has the same key.
In which case, if you are not going to implement TKIP and want to have a free and open network, is there any benefit to implementing a PSK over an unsecured network... |
So I asked this question because I had thought that attackers would have a way to identify client software, because surely if 100 different exploits were spammed against a users machine they would notice?
The answers I got suggest that that is not the case, and indeed the most popular malware kits do just spam a wide v... |
Digital safety deposit boxes: do they exist? if yes, are (any|they) trustworthy?
There are many bricks and mortar financial institutions where one can rent a locked box in a locked room and be assured the contents are secure, that access is constrained and under strict and constant surveillance, and that no one other t... |
I have been told that PING presents a security risk, and it's a good idea to disable/block it on production web servers. Some research tells me that there are indeed security risks. Is it common practice to disable/block PING on publicly visible servers? And does this apply to other members of the ICMP family, like ... |
My understanding is that open source systems are commonly believed to be more secure than closed source systems.
Reasons for taking either approach, or combination of them, include: cultural norms, financial, legal positioning, national security, etc. - all of which in some way relate to the culture's view on the effec... |
We're a small company and we do not have resources that we can dedicate to heavyweight threat modeling. However, if we could find a threat modeling framework that was pretty lightweight I think there is value in documenting the data flows and vulnerabilities that surface from the exercise.
I have looked most closely at... |
Our web application has an error page that displays the absolute URL path and query of the page on which the error occurred, the date/time of the error, and the exception message. (We do not display the stack trace. That is an obvious vulnerability.)
Is it a vulnerability to display exception messages in an error page?... |
I am interested in setting up a captive portal on a wireless network.
From what I understand I would do this by initially having all guests in a temporary vlan, moving them to the real vlan when authenticated or against some other criteria.
What threats should I look out for that people may be able to bypass the captiv... |
The United Nations now considers Internet access a basic human right. [PDF]
Despite the questionable effectiveness of Internet blackouts in silencing a populace and preventing uprisings1, it's worrying that governments can flick a kill switch, as they did in Egypt on 27 January 2011. To that end...
Can concerned citize... |
I'm in the process of designing a system that consists a client application and a single web-service. The client is distributed on several machines (installed by me or a colleague), and the communication between client and server is over the Internet.
What I'm looking for, is a way to ensure that the web-service can on... |
I wanted to know whether its possible to get the MAC address of remote node (computer/Access Point) if I know its IP address.
I have heard that if someone sends you an email (even through gmail), you can find out the IP address (using the email headers), get the MAC address, and find out the exact physical location of ... |
I'm testing sniffing and decrypting my WPA2 wifi network traffic. But when using airdecap to decrypt the capture file (created by airodump) using my WPA passphrase I only get broadcast traffic. If I understand it correctly (after reading the question below) that's because I have to capture session keys when other users... |
We have a public ecommerce website hosted at our datacenter onsite. For people who are within the corporate firewall hitting the website I want to display profiling information about the request of the current page. This would include sql so we want to secure it as much as possible. When accessing the website from insi... |
Looking for a formula and parameters to feed it that will aid in the isolation of relationships within a system when the origin and cause of an exploit within it is unknown. Here's an example of an attack where the vector(s) are unknown, but there is an awareness of the exploit's occurrence: Verifying that I have fully... |
Possible Duplicate:
How can I ensure that I connect to the right wireless Access Point?
Is it true, that WLAN routers aren't authenticated by clients? The only "authentication" is SSID and field strength?
|
How to estimate the time needed to crack RSA encryption? I mean the time needed to crack Rsa encryption with key length of 1024, 2048, 3072, 4096, 5120, 6144, 5120, 7168, 8192, 9216, 10240, 11264, 12288, 13312, 14336, 15360, and 16384?
|
How to exchange RSA public keys safely between two parties via internet?
|
Use of Game Design to Profile Attackers:
Interested in any research that links concepts in game design to security systems in an effort to profile the attacker's identity, motives, skills, etc.; if none exist, willing to except research within the field of game design itself.
UPDATE: Here's an example of what I mean.... |
I'm just started using sqlmap to test for possible SQL injection attacks.
I have got a website which is vulnerable:
C:\Python27>python xxx\sqlmap\sqlmap.py -u http://www.example.com/page.php?id=1
[*] starting at: 19:33:27
[19:33:27] [INFO] using 'xxx\session' as session file
[19:33:27] [INFO] testing connection to th... |
A number of questions on this site mention relying on source IP address as a control and in most of them it is dismissed as being unreliable.
In what circumstances might using source IP address as a control be a potentially useful idea or a bad idea and why.
The idea of "spoofing" the source IP address gets brought u... |
The other day, I got a call from a relative with an email problem. After a bit more discussion, it turns out that two days previously, a man phoned my relative:
stated he was from microsoft;
asked if my relative had some computer problems.
He then proceeded to talk my relative through some "computer stuff" - he can'... |
When creating a new password, people often recommend you use both uppercase and lowercase characters, numbers, and symbols. How does adding any of these increase the strength of a password?
There are 26 lowercase alphabet characters. Lets assume that there are 100 characters in the entire group of capitalized alphabet... |
I am generating a 2048-bit safe prime for a Diffie-Hellman-type key, p such that p and (p-1)/2 are both prime.
How few iterations of Rabin-Miller can I use on both p and (p-1)/2 and still be confident of a cryptographically strong key? In the research I've done I've heard everything from 6 to 64 iterations for 1024-bi... |
You just got hired at company A and the old administrator is no longer there. Requests start coming through for adding users to the internet restrict group. When you look at the groups none of the names make sense and there is no documentation out there to explain what each group has rights to and what it does. That wo... |
On a website I run I have implemented this procedure for account recovery (forgotten password procedure). I would like to know whether there are any issues with it that I have not spotted, that make it insecure.
When the user creates an account, they are required to enter a password (of course) and an email address. Th... |
While performing penetration testing, I got stuck to a point. There is a text field which does not accept more than 20 characters(server side validation). I inserted following piece of code to check XSS (From RSnake's XSS cheat sheet):
'';!--"<XSS>=&{()}
and verified the source for <XSS verses <XSS to see if it is ... |
I have a safe prime generator I'd like to speed up. I can benefit from a significant performance gain if the high order bit in the returned prime can be either 1 or 0. The returned prime would be randomly either 2048- or 2047-bit.
Would this be a problem? Is the possibility of a 2047-bit prime less secure enough to ... |
This is for a Windows 7 Ultimate system, which is not a member of a domain.
When I log into the system locally, I am required to either manually enter my user ID or authenticate with biometrics. The system does not display my username on the Welcome screen at boot-up, or when the session is locked.
In order for this t... |
How does this guy get these cables? Are those cables routed through a single node, where this guy got it? If so, How it is possible? I mean, how that single point came under the control of Julian Assange? If not, then how did he get them? Didn't they encrypted?
Thanks a lot.
|
I have a large scale wireless network secured using WPA/WPA2 Enterprise authentication. Recently, I was made aware of the possibility that someone may use a dd-wrt router and a computer to spoof the wireless network and grab usernames and passwords as devices attempt to connect to it.
To test this theory, I succeeded i... |
The SRP protocol as described by the author assumes that the large safe prime modulus and generator are embedded into the client and server rather than being transmitted as part of the protocol. However, the author suggests in this section that the protocol can be modified to allow the modulus and generator to be chos... |
To initiate a key exchange using the SRP protocol the client sends the username so the server can look up the salt and password verifier. Is there a simple way to change this so that an evesdropper cannot discover the username?
I think an additional Diffie-Hellman could take care of that, but the SRP protocol is so si... |
RFC 2945 (The SRP Authentication and Key Exchange System) states,
The parameter u is a 32-bit unsigned integer which takes its value from the first 32 bits of the SHA1 hash of B, MSB first.
whereas the original publication describing SRP states that u is random.
What benefit is gained from using bits from a hash of B... |
Browsing over this site, many forums, online articles, there's always one specific way we're suggesting to store a password hash:
function (salt, pass) {
return ( StrongHash(salt + pass) );
}
But why this exact way? Why aren't we suggesting to do this?
function (salt, pass) {
return (StrongHash(( StrongHash(salt... |
I am pretty unknown to encryption strategies in production environments. So my concern is to find a solution how to strongly encrypt data, but make it available to multiple users with different keys.
More specific, it is a patient - medical stuff scenario, where patient data is stored encrypted on a server and may onl... |
The SRP protocol as described in RFC 2945 generates the password verifier:
x = SHA(<salt> | SHA(<username> | ":" | <raw password>))`
v = g^x % N
I have three questions: why use SHA twice, why involve the username and why add a separator? Do these add any practical security over x = SHA(<salt> | <raw password>)?
|
Are there high-speed ciphers designed for things like internet streams without sacrificing security? There are so many options that operate in stream mode. How would one choose a cipher?
|
So, i want to enter the security field, and i'm leaning towards security auditing, digital forensics, and reverse engineering.
i'm in school right now, i'm studying x86 ASM, exploring Linux, and soon to be working on understanding exploit development.
i really don't know much about Linux or networking as it is, and i'm... |
In another question, Thomas' answer mentioned the AES-NI instruction set, which piqued my curiosity.
Is there a tool or process available out there to check whether the instruction set is available (besides comparing CPU model numbers)?
|
[Originally on programmers.stackexchange.com with title: Can you encrypt with AES+CBC and search the encrypted data]
Basically, I'm going to go with Advanced Encryption Standard with either Cipher-Block Chaining mode or Cipher Feedback mode or Output Feedback mode (I haven't decided yet). Each mode requires an initiali... |
I am implementing the Secure Remote Password protocol:
U = <username> -->
<-- s = <salt from passwd file>
a = random()
A = g^a % N -->
v = <stored password verifier>
b = rando... |
Own examples:
###############
# KERNEL PARAMETER CONFIGURATION
# PREVENT YOU SYSTEM FROM ANSWERING ICMP ECHO REQUESTS
echo 1 > /proc/sys/net/ipv4/icmp_echo_ignore_all
# DROP ICMP ECHO-REQUEST MESSAGES SENT TO BROADCAST OR MULTICAST ADDRESSES
echo 1 > /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts
# DONT ACCEPT ICMP ... |
Is using a local DNS cache server imore secure than using a DNS server from a router?
|
I am looking for a way how to secure communication between our applications. There is a "server" application listening on some TCP port and "client" application which is communicating with the "server". Both applications are actually installed on some server, there can be multiple load-balanced instances of these appli... |
The encryption library in my programming language does not support CTR, though it supports CBC, CFB, CTS, ECB and OFB. I'm assuming it is theoretically possible to securely implement CTR around one of these other modes.
So I'm wondering, are these quotes describing correct implementation of CTR from a security perspec... |
Recently someone broke into one of our linux servers as a non root user.
An excerpt from .bash_history:
[...]
perl
perl
set +o history
set +o history
set +o history
passwd
sdfsdf
passwd
exit
I assume that set +o history toggles command logging to .bash_history
Is there a way to make it so history logging can't be disa... |
For example, I can log in to stackexchange websites by logging in to external websites such as OpenID, Yahoo, etc. How does this work? How do the websites (SE and Yahoo!, for example) communicate? How does Yahoo! know that it's really stackexchange? How does stackexchange know that I have successfully logged in to Yaho... |
What is the difference between these three? As I understand it, polymorphic malware code actually is always the same, and it's just that it appears to be different (through encryption, data appending/pre-pending), while in metamorphic malware code the code itself gets different each time it propagates (through adding u... |
I have a very basic idea of how these work. I've used them many times when I needed a user management system rather then writing my own. But should I use these for a production system? Would windows user accounts actually provide more security then these accounts in the database tables, given a small user base with ... |
It appears that GSM is like any other technology, and is only as secure as its implementation.
What implementations are known to be secure or insecure due to a fault on the implementor's side, or due to the Moore's law and the ability to easily crack the underlying encryption?
|
For the the client and server to prove to each other that they have the same premaster shared key, the original author suggests this:
M = H(A | B | K) -->
<-- H(A | M | K)
The RFC 2945 recommends this:
M = H(H(N) XOR H(g) | H(U) | s | A | B | K) -->
<-- H(A ... |
I believe it's possible to meet these requirements only if a third party is involved in a manual process. For example:
Each user is given the same public key
The private key resides offline at a third party
Alice creates a document. When she wants to share it, she sends it to the third party who signs the document an... |
Auditd was recommended in an answer to Linux command logging?
The default install on Ubuntu seems to barely log anything. There are several examples that come with it (capp.rules, nispom.rules, stig.rules) but it isn't clear what the performance impact of each would be, nor what sort of environment or assumptions each... |
I've given myself the task of writing code that determines the strength of a password, and really want to break out of a lot of already established ways we do that, as they're often lacking, not designed the right way, or quickly become irrelevant.
Generally, we'll see patterns where you enter a password, and a boolean... |
I can put characters in my password for which there are no keys on a keyboard. On Windows, Alt+#### (with the numpad) inserts the character for whatever code you type in.
When I put this in a password, does it pretty much guarantee that it will never be brute forced? I'm probably not the first to think of this, but a... |
I have several e-mail accounts configured in Thunderbird. I just wanted to move an e-mail from one of my e-mail accounts [A] Trash folder to another accounts [B] Inbox folder. Because the moved e-mail has been lost, Thunderbird doesn't shows it, but here's the catch: Another email appeared in the Inbox of the [B].
I fo... |
A question on Skeptics.SE asks whether current DRM techniques effectively prevent pirating: Is DRM effective?
The question for IT Security is: Can DRM be made effective, and are there any examples?
One approach that has been discussed here leverages hardware support for Trusted Computing - see Status of Trusted Computi... |
Why are people saying that the X Window System is not secure? The OpenBSD team succeeded with privilege separation in 2003; why didn't the "Linux developers" do this?
To be clear: What security design flaws does X have? Why don't the Linux developers separate privileges in X?
|
According to this quote from "applicability" section of PCI DSS it's not:
The primary account number is the
defining factor in the applicability
of PCI DSS requirements. PCI DSS
requirements are applicable if a
primary account number (PAN) is
stored, processed, or transmitted. If
PAN is not stored, process... |
I am a software developer (mostly .NET and Python about 2-3 years exp.) looking to break into the Computer Security field. I have a GWAPT cert and will have both GSSP-NET and Network+ certs by the end of july. I am a member of OWASP and ISSA in order to network and keep up to date on various issues in the field (I atte... |
I have this crazy idea that spam e-mail would not be worth the time of the senders. This is how it's going to work.
Someone sets up a reputation-based site, much like stackexchange sites, where people post stories about how they prank their spammers (or post spammer pranking jobs).
For spam to be useful, they need thei... |
In the last days one could frequently read about attacks from anonymous and LulzSec against different platforms like Sony or HBGary etc. Yesterday for example they DDoS'ed soca.gov.uk and jhw.gov.cn. My question is: How did this work?
Since the PSN is a big network with a lot of traffic in common I'm wondering how much... |
I'm starting to write my first serious web application and am thinking about how to store username and password information. There are plenty of articles detailing how storing plain text passwords is a very bad idea, and salted encrypted passwords are the way to go. However, I can find very little about restricting acc... |
I'm coming up with my next login system for admins of an e-commerce website, which will have this:
login form is SSL secured
password is converted to SHA-256 before being transmitted (bcrypt is too slow still for JS/browser client)
bcrypt stored hashes (I don't want my database if ever stolen to easily be broken)
hash... |
What benefit is gained using a two-pass AE or AEAD scheme rather than a one-pass? Two-pass is roughly half the speed.
|
I noticed that some apps, e.g. Skype, is capable to exit and not run in case one has jailbroken his iOS based device.
I couldn't find online how to check that a device is jailbroken. Please anyhelp from the IT Security community?
Is there other means, other than just closing the app?
|
Scenario: a database of hashed and and salted passwords, including salts for each password, is stolen by a malicious user. Passwords are 6-10 chars long and chosen by non-technical users.
Can this malicious user crack these passwords?
My understanding is that MD5 and SHA-1 are not safe anymore as GPU assisted password ... |
From The EAX Mode of Operation:
We explain the notation used in the definition of OMAC. The value of iL (line 40: i an integer in {2, 4} and L ∈ {0, 1}n) is the n-bit string that is obtained by multiplying L by the n-bit string that represents the number i. The multiplication is done in the finite field GF(2n) using a ca... |
I think I need to correct some misunderstandings I have about AEAD. What is associated data used for in authenticated encryption?
|
Possible Duplicate:
What tools are there to inspect Flash SWF files?
I have decompiled it, verified the source. All seems fine. Appscan also is not able to find anything in this case. But I just want to be sure that I am not missing anything. It would be helpful, if someone can provide some thoughts, hints for penet... |
In the application I'm writing there is need for a huge amount of private data transfer on the order of eighty gigabytes, but there is no public data. I'm looking especially to gain bandwidth/performance benefit by not using an AE scheme that expects associated data.
This is what I'm looking for:
As little bandwidth ... |
Where I work I'm forced to change my password every 90 days. This security measure has been in place in many organizations for as long as I can remember. Is there a specific security vulnerability or attack that this is designed to counter, or are we just following the procedure because "it's the way it has always be... |
Possible Duplicate:
Can you secure a web app from FireSheep without using SSL?
How can I prevent someone on same network from stealing SESSIONID and using it in his own browser (it would mean that he can "log in" without any passwords) without using HTTPS ?
Is there any way in PHP to check/prevent/detect it?
If it's... |
So this is a Vigenere cipher-text
EORLL TQFDI HOEZF CHBQN IFGGQ MBVXM SIMGK NCCSV
WSXYD VTLQS BVBMJ YRTXO JCNXH THWOD FTDCC RMHEH
SNXVY FLSXT ICNXM GUMET HMTUR PENSU TZHMV LODGN
MINKA DTLOG HEVNI DXQUG AZGRM YDEXR TUYRM LYXNZ
ZGJ
The index of coincidence gave a shift of six (6): I know this is right (I used an online ... |
Help me settle an discussion among colleagues and guide future design:
Even in a high impact scenario: e.g. protecting payment application or government gateway but in an Internet accessible application
Is it worthwhile implementing any of the following (or other) measures to protect a username:
Requiring a complex sy... |
getting ready to delve into the technical world of vulnerability assessment, and I have two questions about where to find certain information.
First, I plan on reading "Understanding the Linux Kernel" by Bovet. This book covers Linux memory management, but just to be sure: does it cover EVERYTHING that I will need to k... |
I am interested in how reliable the information determined from doing forensics on a SOHO router is. Most of these routers don't seem to be very advanced, so I question if it would be possible to detect tampering.
If logfiles had been changed for example, could this be detected? Given that they use flash memory, would ... |
Question for any PCI experts out there:
Airport ticket kiosks can use your credit card to find your reservation at checkin time. So clearly PCI must allow use of credit card numbers to identify customers. I assume the airline is storing an irreversible hash of my credit card number with my reservation, and when I visit... |
I've been looking into the OCB cipher mode and everything I hear sounds good. I was planning on implementing it.
Everything except for this lone voice, that is: Collision attacks on OCB:
We show that collision attacks are quite effective on the OCB block
cipher mode. When a collision occurs OCB loses its authentic... |
This question is more of a security policy than a technical security question.
Many years ago I developed an asp.net site, implemented Forms Authentication, and stored the user passwords as MD5 hashs. From following basic security news it's pretty obvious that MD5 is no longer useful. I see two possible plans for handl... |
In a nutshell, let's consider a web application which stores some information in a database as encrypted data. While I'm purposely trying to keep this some what generic, here are some assumptions:
The encrypted data is only stored in the database (not elsewhere). Some fields in a given record are encrypted, some are n... |
When I was a kid, I want to become a Malware Analyst and work in a Antivirus company. At that time, I love to try out different antivirus solutions and did a research project on Computer virus/antivirus back in High school. I'm interested in knowing how malwares got into my system and malware removal.
Today, I'm une... |
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