6
votes
7answers
3k views

Server compromised for 2nd time, cannot locate source of attack

I need some help tracing a vulnerability on my server. For the second time, my server has been compromised with files being replaced with virus-ridden downloads. According to the filesystem dates, ...
4
votes
3answers
2k views

Privilege Escalation Ubuntu

I am trying to learn how an attacker can escalate privileges in Ubuntu 10.04. I have heard that this can be done but no one has ever said how to do it. The best defense is knowing how it is done and ...
6
votes
1answer
3k views

loop-aes or dm-crypt for linux hard encryption?

loop-aes and dm-crypt are both used by partman-crypto for linux hard encryption, but dm-crypt needs no patch to kernel and is more supported. dm-crypt keeps it's key on first hard block, is it a ...
3
votes
2answers
997 views

What are the most challenging IT security certifications to obtain? [closed]

Which IT security certifications are considered the most difficult to obtain?
3
votes
2answers
1k views

Statistical data about the performance of various encryption algorithms

How can I find statistical data about the performance of various encryption systems, such as RSA, DSA, ECC etc?
5
votes
2answers
375 views

System for Mutual authenticaion and confidentiality

I am looking for a protocol where there needs to be mutual authentication between client and server. For example server should connect to a particular client only. That is client should authenticate ...
16
votes
1answer
2k views

Timing attacks on password hashes

Timing attacks can have a devastating impact in scenarios where the secret is involved, often in cases where byte-wise array comparison is used. Now there are those that advertise using constant ...
1
vote
3answers
2k views

How can I use a VPN to protect my privacy

How should I configure a VPN in order to access blocked websites and to hide my identity? Usually I use SSH tunneling to protect my privacy and to escape censorship. I know nothing else about VPNs ...
3
votes
1answer
242 views

Do any cloud storage system offer an append-only mode for buckets, directories, etc.?

I'm curious what cloud storage systems offer an append only mode, especially open source ones. In particular, would any cloud storage systems support the following workflow : Anonymous users may ...
3
votes
1answer
3k views

My web server is hit by strange traffic, what is that?

I'm a noob and just set-up a linode account to play around with linux development. I started nginx and made a simple homepage for my domain (giuliopizzini.com). Today I checked the nginx logs and ...
1
vote
1answer
276 views

Can HIPS software practically be considered a form of MAC

Host Intrusion Prevention Software can restrict applications from taking certain actions regardless if they have the privileged to do so as assigned by the operating system. Given that with the use ...
6
votes
5answers
870 views

What is the practical difference between MAC and Capabilities

Both Mandatory Access Controls and Capabilities allow for fine grained privileges to be assigned to applications irrespective or in place of privileges inherited by the running user. Is there any ...
4
votes
1answer
239 views

Computer team's password change time different from other users?

We need to determine a password policy for our organization. All users, in general, will have 90 days until they will have to change their passwords, complexity required and passwords need to be at ...
14
votes
3answers
734 views

can I identify the origin computer for a program?

I am Developing a program in several platforms and languages, But I don't want anybody to discover the origin computer where the program was developed, is there any way that someone (especially the ...
4
votes
1answer
260 views

Using EventStore For PCI Compliance?

I have been hearing a lot of good things about EventStore 3 and am looking to upgrade my server event forwarding systems for PCI compliance next year and was wondering if anyone had looked at the ...
10
votes
3answers
10k 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?
10
votes
2answers
274 views

How to protect against exploitation using a lapsed domain

Consider a domain that had been in active use for some time but is no longer desired — perhaps the company is out of business or a name change took place years ago, or whatever. The domain ...
4
votes
1answer
521 views

Logging True/False Negatives on Snort

I'm using Snort in a lab environmnet with artificially generated traffic. I'm looking to build a confusion matrix from known generated attacks. True Positives and False Positives are easy to parse ...
2
votes
1answer
6k views

Is 4096 bit good enough to encrypt data?

I need to store encrypted information in a mysql table. I would like to use the AES algoritm but I don't know if 4096 is supported and if it is a good length to encrypt data like: credit card, email ...
13
votes
3answers
262 views

What is a reasonable approach for deidentifying data?

I have been asked by a client to deidentify the PHI data in their database and I'm either over-simplifying the process or my client is overly paranoid. Perhaps you can tell me which is the case. ...
4
votes
4answers
3k views

Is it correct to use form field(hidden) for storing Session Token

Is it correct to use form field(hidden) for storing Session Token instead of using Cookies? What is the security risk associated with it?
2
votes
1answer
721 views

How can credit cards be encrypted and still be recalled later?

Many merchants offer to save credit card info in an encrypted form for faster checkouts from their store in the future. How is it that merchants can store this information in an encrypted format and ...
3
votes
1answer
1k views

Purpose of certificates signed and trusted by CA

Another newbie question but I just don't get the purpose of certificates signed and trusted by CA. We already have public/private keys, hash functions to sign/encrypt messages so why do we need ...
2
votes
3answers
2k views

HTTPS Apache2 Information Leakage

Hello IT Security! I have Apache2 vhost with HTTPS listening on port 443, ie. https:// securesecret.com. I have another vhosts with HTTP listening on port 80, ie. http:// one.com, http:// two.com. ...
2
votes
4answers
1k views

Best way to push data to a client without being blocked by firewall

I'm asking this question here since I think people on this forum probably have the best knowledge of firewalls and routers. Say I'm designing a multi-player game and I want to push data to the client ...
5
votes
3answers
341 views

How do I defend against known php hacks

I have IPs attempting to probe our web server trying to find open URLs. The two known methods are attempting to find specific nodes on our drupal site, or attempting the ../../../../ trick to try and ...
10
votes
4answers
364 views

Should a web application return true http errors?

Exception and error information can be used by a malicious user to map out the API of an web application, so it is routine to see security checklists to advise returning only a "Please contact your ...
1
vote
1answer
1k 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?
4
votes
2answers
2k views

Incrementing Initialization vector by 1

Suppose that we do not generate initialization vectors randomly (using AES in CBC mode). Instead it is initially all zeroes and we increment it by 1 each time a message is encrypted. How can this ...
6
votes
3answers
627 views

Is the Kaminsky bug still a problem for sites without DNSSEC?

I have read about the Kaminsky bug, but I don't fully understand how easy it is to use this vulnerability for an attacker. Are DNS-software updated now so it's not that easy to use this vulnerability ...
1
vote
2answers
3k views

Best efficient windows hardening audit script [closed]

Do anyone know of a script that uses no 3rd party executables (preferably a batch file) that can be used to audit windows machine state securitywise? (including best practices features - gpo, ...
3
votes
3answers
2k views

how an iframe can cause xsrf?

I know how a form tag is prone to CSRF which does not use any token (or any other challenge-response mechanism) but I was wondering how an iFrame can be used to cause XSRF attack and what would be the ...
0
votes
3answers
527 views

DOM XSS : Need Help

I was trying my hands at DOM based XSS. I came across a scenario where user controlled string from the URL is included in javascript as below var userControlled=substring of URL; ...
2
votes
2answers
231 views

Securing iPads and laptops in an enterprise

We have users in our organization who own iPads and we'd like to connect them to the network; however, if the users download and store sensitive data on the devices, that can pose a security issue. Is ...
7
votes
2answers
1k views

Best practices for email security

I writing a security layer for my app and I would like your input on updating users' email addresses (also used for the login). I'm interested to hear from anyone who has written an application with ...
3
votes
2answers
177 views

How do shared hosts protect different sites?

I host all my websites from a single VPN, and am about to sell some limited space of my Linode to a friend to host their new blog. It'll simply be another entry in Apache, and then a dedicated folder ...
0
votes
3answers
2k views

Number of AES-256 operations per second on a maximized Cray XE6

How many FLOPs does one AES-256 operation take in ECB mode? How many AES-256 operations in ECB mode can a maximized Cray XE6 perform per second? Cray states that it can be scaled to over 1 million ...
1
vote
1answer
1k 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 ...
3
votes
4answers
239 views

what is the use of stolen personal details?

What can hackers do with personal information that includes this: First name, last name, snail mail address, mobile phone number and email address?
6
votes
2answers
2k views

What algorithms are best be cracked by GPU?

What algorithms are best being attacked by a GPU powered password cracker? For example, I heard that md5crypt that is being used in unix shadow file, is not the best choice for GPU cracking because it ...
6
votes
3answers
2k views

Is it possible to infer that a hidden truecrypt partition is likely to be present

Truecrypt contains a feature that let's you create a hidden volume. It's said that it can't be proven if a hidden volume exists. However, is it possible to infer from the state of the data on the ...
6
votes
2answers
834 views

Two certificates on smart card

I have a question regarding Swedish gov eID (but I guess it is a pki/smart card general question); Why is there two certificates/keys on the card? Background: In Sweden you can have a "citizen ...
4
votes
2answers
214 views

Salting a public hash

Does it make any sense at all to salt a hash which might be available publicly? It doesn't really make sense to me, but does anyone actually do that? UPDATE - Some more info: An acquaintance of ...
22
votes
4answers
29k views

What is the use of stolen credit card details?

What can a person with stolen credit card details do? Buy porn? Buy tons of server resources to perform an attack? What else? I'm sure that if he buys books, shoes and bicycles or transfer funds ...
2
votes
1answer
3k views

Detected Port Scanning Attack in ESET Smart Security

I receive a number of notifications from ESET Smart Security about Port Scanning attack. But I'm behind a router. But as far as I know, computers behind a router is not accessible from others (Please ...
1
vote
2answers
835 views

How to react on a message about a pending account ban on Facebook? [closed]

Are you getting this message on chat? LAST WARNING : Your account is reported to have violated the policies that are considered annoying or insulting Facebook users. Until we system will disable ...
3
votes
1answer
3k views

Is opening both TCP/UDP less secured than just TCP or UDP when needed and why?

If application needs opened port X UDP, or X TCP combination. Is there any potential risk by opening both UDP/TCP as I usually am not sure which one the application uses?
9
votes
2answers
130 views

Encouraging security researchers to disclose vulnerabilities

What are approaches to forming solid relationships with security researchers? For example, is publishing a public PGP key on the "contact us" page of a company's website for high levels of risk ...
6
votes
2answers
563 views

International pentester certification

I've looked at the questions regarding certifications on this site and they are essentially asking what to go for. I hope that my question is distinct enough that is is not considered a dupe. I ...
30
votes
4answers
10k views

Can web sites detect whether you are using private browsing mode?

Most modern browsers support "private browsing mode" (also known in Chrome as "Incognito mode"), where the browser does not save any information to disk about your browsing while in this mode. In ...

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