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Im using php and I was looking to store passwords in a mysql database. I was wondering what would be safer to use a salted hash or openssl encryption? If i use a unique random generated salted hash for each user and store the salt on the database, is there a way someone can find out the salt and decrypt it? Or if I use... |
I was recently reading An Introduction to Hardware-Assisted Virtual Machine (HVM) Rootkits (PDF), and it wasn't entirely clear about the conditions under which the hypervisor rootkit can start virtualization. If virtualization is enabled then everything is fine, but what happens if virtualization is disabled?
Specific... |
This may be a naive question. If it is, I'm fine with just a link to outside information. I studied RSA encryption about 2 years ago, but that's about it.
I'm just wondering: is it a matter of engineering or is it a fundamental problem? By the latter, I mean "will we always be forced to release information which could ... |
The following MSFT document has this paragraph:
All possible certificate chains are built using locally cached certificates. If none of the certificate chains ends in a self-signed
certificate, CryptoAPI then selects the best possible chain and
attempt to retrieve issuer certificates specified in the authority
... |
In "How Certificate Revocation Works" a brief mention of Attribute Certificate and Reason Code partition is made:
If validated by a client that supports partitioned and indirect CRLs,
the IDP extension enables the client to determine the necessary scope
of a CRL when a CA certificate is renewed or re-keyed. For Wi... |
I'd like to enable the most secure OCSP validation that Windows 2008 SP1 and newer support.
Based on the following information, am I required to implement id-pkix-ocsp-nocheck on my OCSP certificate?
If so, does that mean an OCSP response can be forged, allowing an revoked certificate to go unnoticed by the victim... |
Even after I purge all my Internet temporary files, I still see information when I type
certutil -urlcache
How do I purge this information?
|
Some highly secure networks and DMZs prevent all communication to outside hosts. This can cause issues with validating externally signed data
I can guess that issues with signature validation occur when checking the certificates' CRL and OCSP data in many areas such as
Authenticode & signed Powershell objects
Authen... |
Windows seems to be saving my credentials for a variety of applications (terminal servers, etc) and I'd like to purge this data.
How can I backup and purge this data?
|
So if someone steals my (ex.: I didn't teared up a piece of paper that had these and I throwed it away on the street) ID's like my:
Full name
Permanent address
Birth date/place
My mothers name
Identification card number
Telephone number
What bad could happen to my ID's?
|
Password space is quiet small. Therefore slow hash should be applied to password before using it for encryption.
Should slow hash function (like bcrypt) be applied to password before using it with OpenPGP/GnuPG? Do they do it itself?
|
This document describes how there are 3 ways to constrain a SmartCard certificate
The Enhanced Key Usage field defines one or more purposes for which
the public key may be used. RFC 5280 states “in general, [sic] the EKU
extension will appear only in end entity certificates.” Certification
authorities’ certifica... |
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 does it affect GnuPG security? It gives me an option to encrypt files with a right-click on Ubuntu.
**[mod note: link removed since we no longer analyse code]
|
Is it worth separating www-data and apache service from each other, in jails?
I currently have this setup:
Freebsd 9
1x Public ip (jails are in private ip's, nat'ed)
2 separate domains, managed by 1 person each.
Jail1: apache service
Jail2: mysql service + database files
I've been thinking about adding:
Jail3: www-d... |
Are there any windows based pen testing vms out there similar to Metasploitable based on ubuntu?
Just starting to learn hacking and such a box would be very helpful.
|
The following paragraph from MSFT Best Practices for 2003 PKI says Windows 2000 authenticated via RPC vs 2003 that authenticates using DCOM
A CA running Windows Server 2003, Enterprise Edition, uses DCOM and Kerberos impersonation for authenticating requesters. It compares the client token against an access control li... |
If I understand this correctly, when I use a cryptographic (hardware) engine, I have to trust it. Are there any cryptographic algorithms with properties that allow me to verify the correctness of an engine in a computationally cheaper way than to do the same work myself?
EDIT:
In my paranoid reality I assume the engine... |
Today, Microsoft released a security advisory warning that the "Flame" malware exploited a weakness in a cryptographic algorithm used by Microsoft Terminal Server Licensing Service, and was thereby able to get some of its code signed so it appeared to have come from Microsoft.
Here's what Microsoft wrote:
We have disc... |
I installed XAMPP on my development PC, and started Apache HTTP server and MySQL.
It comes with a test page "CD collection", with the following back-end PHP code:
mysql_query("DELETE FROM cds WHERE id=".round($_REQUEST['id']));
I'm not an expert in PHP, I'm guessing the round call is there to prevent SQL injection. S... |
I am interested in storing certificates for various purposes on a SmartCard. Since this answer illustrates how there are confusing differences and similarities between RSA and AES
When should one class be used over the other to get the most interoperability? If the class doesn't matter so much as the settings, what ... |
I am looking for facts and figures of research or surveys done which have bench-marked Snort with other IDS/IPS on various parameters like overall performance, accuracy, speed, documentation, scalability etc.
|
I'm building web-app. And i have concern about security issues.
In world a lot of similar questions, but many of them does not have really clear answer(advise,suggestion). This is the reason why i made this question.
I have login page with username and password. User will POST them by HTTPS.
Server will compare it with... |
When I use gpg --symmetric --s2k- and press tab some options appear:
--s2k-cipher-algo
--s2k-count
--s2k-digest-algo
--s2k-mode
What do those options do?
|
The IPSec tunnel creation process involves 2 steps:
The ISAKMP Phase
The IPSec Phase
What is the reasoning behind having the two phases? From what i see, the first phase is already encrypted using pre-negotiated keys and the tunnel established is used to negotiate the parameters for the second tunnel.
If the first phas... |
We plan in distribute Node.JS webservers, for their advantage of async I/O. The Node.JS https servers use OpenSSL libraries.
It appears that OpenSSL has vulnerabilities resolved on a regular basis. This makes me wonder if I should move the SSL layer to a separate Java process / something more proven, that will not have... |
I have a linux webhosting server which affects a high DDOS.
I want to use Cisco ASA 5500 Series Adaptive Security Appliances to protect the linux server from this DDOS. I know there are many factors should you know before you choose the suitable hardware firewall like the amount of this DDOS and pps ..etc
Please sugges... |
In short what security features exist that I should look for in a smart card?
What physical features exist, which are important?
It appears smart cards may exhibit different levels of wear and tear from normal use, or that of harsh environments, or keeping it in a wallet. Ultimately this usage may cause card fai... |
What kind of things would you check in a domain and IP scoring system? Which things are the most important?
If I have a web site or web service, I would like to figure out a score for my visitor. If their score is below a certain score I will present them will extra security measures such as a CAPTCHA or block them alt... |
A sad story: One of our hard drives failed. While it was failing, we managed to take a quick backup. As it is our standard practice, we encrypted the backup using GPG (by however method Duplicity uses to do that, most likely plain gpg -c). Unfortunately, we stored the wrong passphrase. (Doh!)
The backup contains some ... |
My bank proposes certificate. They say I will be able to use it only on one computer. I don't understand: can't I use same certificate on several machines by exporting and reimporting it ?
|
I currently have a network set up with WPA2 and AES encryption, the password is 8 characters long but was randomly generated and contains no dictionary words. However I'm concerned about the increasing power of computers and their ability to crack handshakes, as such I was considering increasing the length.
I'm aware t... |
I have an account with Google & Facebook. Login IDs for them both are same (same gmail id).
When logging into StackOverflow using either of Google or Facebook logins would link to same account.
How does that work?
|
I am building an application that requires secure data transfer. In particular, the sender has a data file that needs to be sent to the receiver. It is required that only the receiver be able to read the data. It is also required that the receiver can know for sure that the data comes from the sender.
The sender and re... |
I would know if it is secure to centralize database information into one file like this :
db_infos.php:
$server = "localhost";
$user = "root";
$password = "1234";
$database = "foo";
$table = "bar";
And then, include this file when I need to:
include("db_infos.php');
mysql_connect($server, $user, $password);
...
Is th... |
Some bank sites force me to use system generated numerical login (ie. 8 digit number). Apart from singnificantly decreasing usability and giving impression of security (to some), does it serve any purpose?
Isn't the security aspect illusionary, since decreasing probability of guessing the credentials can be as well en... |
I'm thinking about the safest possible way to store secure data (eg. Credit Card numbers) with a requirement of sending them in clear text to third party API (so hashing doesn't come into play).
I've came to solution that seems to be more secure than typical 'store them encrypted and decrypt when you have to use them u... |
If you wanted to block access of a single machine to all sites whose domain is owned or controlled by Google, how would you go about generating a comprehensive list to add to /etc/hosts? How would you handle Google Apps sites?
|
What root certificates are/are not updated when the following checkbox is checked?
Additional questions
If I manually remove a root certificate, will this service replace that very certificate?
What is the equivalent in Windows 2008R2/Win7, I can't find the setting?
|
This article says:
"Finding collisions is a tricky process, since it requires you to muck
with the bits of the public key embedded in the certificate (see this
paper for more details). Also, Microsoft could have prevented this
somewhat by adding a random serial number to the cert, which they
didn't do."
My qu... |
My assumption is that S/MIME almost always utilizes certificates as follows:
My certificate can be used to allow people to encrypt messages and send them to me.
My certificate (the same certificate) is used by me to sign messages and send them.
Is there an RFC reference that specifies this is a requirement for S/MI... |
How can I know that a network card in a server was infected by a virus or not? Are there any methods to check it?
|
Normally, I'd say yes, api keys should be kept secret, and Google's api console even says that. However, I'm just making an ajax get call and all the info is in the clear on my page in order to construct that query, including my api key and cx(custom search engine id). Presumably, someone else can use my credentials ... |
I love using Python for the scripts I need and for work. But I really want to learn Python for network security since I will start a NS course next year.
My question would be how would it be the best way to learn? I was thinking of starting by writing a network sniffer or a like, but I think this is a bit to high to st... |
Every Windows 7 host has a Trusted Root certificate from Entrust that has the "Netscape Cert Type" extension (see image)
I'm comparing inter-operable S/MIME extensions and see a pretty diverse set of offerings and configurations.
Are there clients that still refer to this extension? Is the Netscape extension needed o... |
Consider the following requirement:
Bob should be able to verify that a payment request came from Alice.
The above is in simple terms the basic idea, however, in reality Alice would be user A of company XYZ and Bob would be a registered vendor for company XYZ.
My thinking on this was for each company that registers w... |
Could XSS lead us to the Local File Include or Remote File Include?
I read article that it's possible to upload shell via XSS vulnerability, but I still have no idea how it had been achieved.
|
Suppose I encounter a trusted PGP key that isn't really who they say they are. I don't want to sign their key and promote that entity.
Can I somehow show my dissidence from the trust that everyone else is giving? I didn't see anything obvious on the Wikipedia page.
If the answer is "no", is there any research that illu... |
How can I check if an extension/addon consist of malware code? Is it easy to detect if it collects sensitive data (like spyware), logging keystrokes and so on? Can AV recognize malware extension as "bad"? Can an extension exploit browser vulnerabilities?
|
I am just a mere mortal that wants to have a somewhat secure way of managing all my passwords.
This is something that I have been putting off, but since LinkedIn decided to give away one of my passwords away, I figured it was about time I addressed this issue.
I say somewhat secure, because - clearly - the most secure ... |
I'm writing a multi-tenant application where accounts are scoped by subdomains. This adds considerable complexity and I'm starting to worry about security.
Each user can have several accounts. For example, assuming acme.com is my app, elmer.acme.com and fudd.acme.com can belong to the same user. When logged in, users c... |
In the past I used varchar(255) for storing hashed passwords (no salt). Is this still enough? Or are longer fields required?
|
AES is a standard encryption routine that can be used consistently across multiple languages, assuming all the variables match up. My question is, what are the variables. I am aware of the following
Variant (is this AES-256, or just plain AES-128)
Data to encrypt
Key (128 bits is common)
Initialization Vector - now wh... |
If a Java-based webpage takes a user-supplied parameter and instantiates an object using Class.forName(parameter)
What's the worst possible consequence?
The attacker does obtain stack traces. After the object is instantiated, it is cast to a proprietary class, so it will throw exception at that point.
Example consequ... |
A number of texts signify that the most important aspects offered by a DBMS are availability, integrity, and secrecy. As part of a homework assignment I have been tasked with mentioning attacks which would affect each aspect. This is what I have come up with - are they any good?
Availability - DDOS attack
Secrecy - SQ... |
How should I document the results of a security code review?
Does anyone know of any resources for reviewers that provide guidance on how they should document their findings? Maybe a document that describes best practices or makes recommendations about the best way to do it? Or, does anyone here have any recommendati... |
I have a wireless camera in my network. Running nmap on the camera, I discovered that the port 1010 is open but I could not find what it is used for. I looked in the administration pannel and did not find any application that was configured to use that port. With nmap or wireshark, it is qualified as "surf".
I can conn... |
Does anyone know of a short security quiz that could be administered online, to test the security knowledge of a developer? I'm looking for something simple to administer and simple to grade, ideally something that would take a developer only a few minutes, as a screening tool to differentiate folks who have no experi... |
I want to write a simple file shredder in c++, i.e. a program that deletes a file so that it is not recoverable. Would the following be a secure and correct way to do that?
(1) Open the file with
ofstream myfile;
myfile.open ("deleteme.txt", ios::out | ios::binary);
(2) Then run through 10 rounds of something like
un... |
How should I defend against this type of attack? This is a tightvnc logfile excerpt from a linode cloud server running Ubuntu 12.04 (Precise) with the ubuntu-desktop package added to the bare server. By default this Ubuntu linode cloud server has exactly one user named root. No other users will ever be needed for th... |
leakedin.org claims to offer a service checking if your LinkedIn password has been stolen and whether it has been cracked.
The website claims that it's pure Javascript, that is your password won't leave your computer, and says you can provide a SHA-1'd password if you want. But I don't know the people who created leake... |
Can some one simply explain the meanings and the difference between symmetric key and block size.
Why 64 block size not safe any more and they increase it to 128 (AES,...,Serpent)? And what about key size?
|
Does "password entropy" only mean that it's long and/or looks random, or is there something else? If the password contains 50 random numbers, will it be high entropy or not?
|
This question doesn't fit well in many categories but hopefully someone's run into it before.
I'm developing a web api that will interact with a physical device. Each new physical device has it's own unique ID, but those IDs are guessable (essentially they are sequential as they come off the assembly line.)
When the ... |
It's still a commonly recommended way of hashing passwords, even if its insecurity had been proven in 1996:
Therefore we suggest that in the future MD5 should no longer be implemented in applications like signature schemes, where a collision-resistant hash function is required. According to our present knowledge, the ... |
I just installed 'mcrypt'. When I try to encrypt some file with DES using the command 'mcrypt -a des myfile', I am prompted for a passphrase with a maximum character count of 512.
> mcrypt -a des myfile
> Enter the passphrase (maximum of 512 characters)
How can DES support 512 characters or is there something wrong wi... |
Windows 7 clients (and older) don't support NONCES, a key feature used in securing the revocation check. Without a NONCE a MITM could replay a previously signed response and alter the validation of the certificate.
What mitigations are there to prevent OCSP replay attacks on a client that doesn't support NONCES?
More ... |
This malware directs your computer to use DNS servers under control of the badguys. These DNS servers were taken over by the FBI. They were replaced with clean ones, to prevent service disruption, but this taxpayer funded service will be discontinued July 9.
Sites like Google, and dns-ok.us have some way of knowing whe... |
I use Win Xp Home with SP3 and am pretty aware of security problems. I use Palemoon 12.1, a version of Firefox optimized for windows.
I usually use printfriendly bookmarklet to create printable pages or to print pdf from web:
I was curious to test it on the Anubis executable checker and I know of these possible proble... |
Charity has a server in their office onto which they backup a database with sensitive information. They want to get rid of this server.
Is there a cost effective solution that would allow them to comply with UK Data Protection Act?
Currently I think about encrypted version stored at Dropbox.
|
Vulnerability I am referring to is:
http://www.securityfocus.com/bid/51830
And here in more detail:
http://auntitled.blogspot.com/2012/02/mini-poc-for-php-rce-cve-2012-0830.html
So basically what it amounts to is that in the code someone forgot to add an "else" statement and it allows an attacker-controlled string to b... |
A lot of rootkits for Windows (maybe even Linux?) do hide in drivers. Why is that?
One reason I can think of is that using a driver they run in kernel mode and have full system access, but aren't there easier ways to accomplish this? Or are there even other reasons?
|
I am currently on a IPv4 network. The IPv4 network is accessed by a router, which gives my machines IPv4 addresses via NAT.
On one of the machines, a Windows 2008 64-bit machine, I have set up a IPv6 tunnel. This allows me to access IPv6 sites by using IPv6 to IPv4 tunnelling to a IPv4 server, which de-encapsulate the ... |
The recent, widely publicized security incident where millions of Linkedin were exposed reminded me to tighten up my password practices. I'm looking at several password managers now and I'm especially curious about Lastpass.
They write on their homepage:
LastPass is an evolved Host Proof hosted solution, which avoids ... |
By visiting: http://nvd.nist.gov/cvsseq2.htm I noticed that the CVSS attributes the following impact values for confidentiality, integrity and availability:
none : 0.0
partial impact : 0.275
complete: 0.660
So, I would like to understand why is this given a value of 0.66 for a full impact? Why the... |
Looking for suggestions on implementing a server-side lookup table, where the key is an email address.
Goal: Keep these email address private, even if data on the server is stolen.
Assumptions: The server does not need (and ideally should not know) the email address. Clients cannot directly talk to each other, but it's... |
I just wanted to know if you can increase the cost (iterations) of those two algorithms off-line.
I want to increase the cost every year of my users passwords.
One solution is to recalculate them when the user logs in, but a user may have not logged in that period, and I don't want to wait till he logs in.
This could b... |
In http://www.freebsd.org/doc/handbook/kerberos5.html section 15.7.8.3 “The KDC is a Single Point of Failure” you can read:
By design, the KDC must be as secure as the master password database is contained on it. The KDC should have absolutely no other services running on it and should be physically secured. The dange... |
If you've got a website aimed at people that are not necessarily technically proficient, letting new users choose their own password isn't very secure because of the simple fact that a lot of people don't choose secure passwords. Some methods of dealing with this problem are:
Most common: have a 'password strength che... |
Is DWR considered secure, or what may be required to secure Direct Web Remoting?
Are there better options for hardened asynchronous communication?
|
Background
Many developers are unnecessarily lowering the security of the event log, or requiring applications to run in Administrator mode just so they can use the event log with this C# or VB code:
EventLog.[WriteEntry][1]("MyBadApp", "This will cause an exception for ASP.NET and non admins", EventLogEntryType.Erro... |
Suppose we have an image with some hidden info behind it. If we open it in a photo manipulation software like Photoshop or Gimp, without editing it and just save it as a new image, does the image still contain the secret info?
|
I'm sorry if this is a dumb question. I'm new to all this.
I have a large number of users. I need to be able to generate SSL certs for various internal domain names. All of these certs need to be accepted by the browsers. It is my understanding that I need to generate a Certificate Authority like this article shows... |
What are the various advantages of using extended validation (EV) certificates than normal certificates which also provide comparatively high degree of encryption like RC4, 128 Bit?
I know that the browser shows green flag for EV certs. But is there any other benefit than just that?
|
Is there any part related to penetration that OSCP/OSCE fail to cover in their training programs?
How much will I be exposed to penetration techniques after completing OSCP/OSCE?
|
I'm reading the wikipedia definition about bcrypt but I don't understand the meaning of 'adaptative' and 'over time it can be made slower'. Can someone explain what they mean in this situation?
|
If you forget your LastPass master password then LastPass provides the possibility to recover access to your vault using a One-Time-Password (OTP) which is stored locally but is initially disabled.
The procedure is described here:
http://helpdesk.lastpass.com/account-recovery/
It goes along these lines:
Go to the ac... |
An email claiming to be from facebook had the following content:
Hi Andrew,
You recently requested a new password for your Facebook account. It looks like we sent you an email with a link to reset your password a few days ago. This is a reminder that you can log back into your account at any time by clicking this li... |
As far as I know, AH only covers integrity and authentication. So, suppose that an intermediate router receives the packet with AH and not ESP. Then, can't the router open its content (<- and that's obvious) and even read authentication data of the packet and use it to fake its identity? (and make replay attacks possib... |
I have to present a paper and make a presentation about the principal types of attacks by port scanning. What literature do you recommend to cover enough information about: types of attacks, port security, vulnerability of ports, protection against attack, etc.
|
Per my understanding about SSL's, a user has to send his CSR to a CA (Verisign) to get it signed, and Verisign will send the sign X.509 certificate in return.
What I don't understand is what, exactly, Verisign does with the CSR file? In the event that I lose the x509 certificate sent by them, will they be able to gener... |
I am currently a Masters student looking to change career from sales to IT, specifically Information Security. What are some good resources about finding jobs? What skills should I focus on to get a security job?
|
The Elcomsoft "Advanced EFS Data Recovery" whitepaper says
First the program tries to do this automatically, for example trying to extract the password from cache or system files, checking simple combinations (such as password=username) and then conducts an attack using a medium-sized built-in dictionary.
What's the ... |
I am looking for a really secure password manager and I really like the fact that Password Safe supports encryption/decryption using a Yubikey programmed in challenge-response mode.
Read more here:
http://www.yubico.com/passwordsafe
Other password managers support Yubikey for login to your online vault (using Yubikey... |
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 group called dba, and added the user to that group.
So my question is, if the ora112 user's umask is set to 077, then no... |
I need to have more details about CVE-2012-0883 vulnerability published on : http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2012-0883
Second, I need to know , what mean DSos mentioned on the Overview section.
Is it necessary to have another vulnerability which allows an attacker to create an illicit dynamic lib... |
I've had a request that we upgrade all our internally developed applications to .NET v4.0.
Needless to say, this is a massive chunk of work. Is using applications based on the .NET framework prior to v4.0 a genuine security issue?
|
Given the size of a TCP packet is 60 bytes, there is a SYN Flood attack on a computer made by a 100 Mb bandwidth, the question is how many syn packets are sent in a second? Is there any formula for calculating?
|
In this interview posted on Krebs on Security, this question was asked and answered:
BK: I’ve heard people say, you know this probably would not have
happened if LinkedIn and others had salted the passwords — or added
some randomness to each of the passwords, thus forcing attackers to
expend more resources to cr... |
What are the advantages/disadvantages of OpenNIC vs ISP for DNS resolution with regards to security and privacy?
|
An e-mail provider provides people with usernames for e-mail accounts. That normally means that they have access to your e-mail if it is unencrypted.
Likewise, do sip registrars have access to people's conversation when they voip each other? Or when you use your sip account to call a regular phone through a third party... |
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