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7
votes
1answer
766 views

Open Problems in Security?

I know it might seem a bit too much theoretical, but I was wondering if there was some list of known open problems in security? In a similar way that there are open problems in Theoretical Computer ...
2
votes
1answer
49 views

Long passwords and key derivation functions

Not being a security expert, I have a rather theoratical question that I have been thinking about for quite a while now: Let's imagine an encryption software that takes a user-provided password, ...
3
votes
1answer
190 views

Safety in Access Control Matrix and Take-Grant Model

I'm learning about the Take-Grant Model and Access Control Matrix, and I have a couple of questions regarding leaking and the safety question. Definitions These are the definitions I am using (see ...
3
votes
2answers
78 views

Do `sudo` and `su` belong to capability-based security?

In Linux, do sudo and su belong to Capability-based security ? For example, when editing a system file, we usually need sudo or su to temporarily switch to user root. Does this example belong to ...
4
votes
1answer
27 views

Capability-based security vs protection rings: in what sense are they diametrically opposite?

From http://en.wikipedia.org/wiki/Capability-based_security Capability-based security is to be contrasted with an approach that uses hierarchical protection domains. From ...
1
vote
2answers
43 views

ISAKMP and OSI layer

I'm trying to find out on which OSI layer the ISAKMP protocol resides on? It isn't listed under the wiki's list of network protocols, and the internet says it's either on the transport, network or ...
1
vote
2answers
804 views

authorization vs federation vs entitlement

I am vague among the three following terms: authorization, federation, entitlement (as stated by the OpenAM product: OpenAM provides open source Authentication, Authorization, Entitlement and ...
6
votes
1answer
4k views

Will double encryption increase the security of cipher vs bruteforce?

Assume I have a function encrypt(mes,key) where mes is the message, and key is the key. The length of key is 64 bits. Last but not least: assume the only way to crack my cipher is a brute-force ...
1
vote
1answer
686 views

Nowadays, what is the difference between Cyber Security and IT Security? [closed]

Lately (and not so lately), you can hear a lot about cyber security. It is really hard to find an official description about this matter so, let's take the ISO 27032 description: "Cybersecurity” ...
4
votes
1answer
65 views

Principles of memory forensics tools

I am currently writing a thesis about digital forensics which includes a chapter about memory forensics. Besides the tools and the methods of acquiring various data with them, I am kind of desperate ...
3
votes
1answer
76 views

How long do HTML password fields (sent to the server as postdata) remain in memory?

In any major server-side web framework, there is usually a mechanism to read HTML form input, e.g. in ASP, for an HTML element, <input type="text" name="the_field" />, it is ...
40
votes
2answers
9k views

Amount of simple operations that is safely out of reach for all humanity?

Cryptographic primitives usually assert some security level given as number of operations to mount an attack. Hash functions, for example, give different security levels for collision attacks, ...
1
vote
1answer
71 views

Any known protocol for establishing trust between an inherently untrustworthy source and a server without a 3rd party?

Is there any kind of protocol, scheme, or theoretical paper out there that implements or examines the problem of establishing trust between two parties (communicating, listening) where the ...
4
votes
3answers
373 views

Fully encrypted social network theory

I have this idea about building a social network that stores all its data encrypted. The idea is that a member's data is stored on multiple 'base servers' (of the member's choice). Each member has 3 ...
28
votes
7answers
13k views

Where can I learn cryptography/cryptanalysis the hard way, without going to school ? Any good book?

I'm not so bad at mathematics: I know what are p-list and p-combinations, I know matrix algebra, I know what a XOR is, I know how to tell if number is a prime, etc: I'm not the programmer who hates ...
15
votes
4answers
1k views

Future proof encryption possible in theory?

Let's say I have a message that I want to keep safe for the next 100 years. Is it theoretically possible? Let's say the message is unique (raw picture data, raw video video data, raw text data) and ...
1
vote
4answers
327 views

Strategies to store/remember very long password?

If future proof encryption is - in theory - possible it will require long password. What are some of the strategies for storing or remembering very long - in this case rarely used - password? For ...
8
votes
2answers
262 views

What applicability does the Halting Problem have to infosec?

I was reading an infosec blog recently, and I was caught off guard by the following statement: Sure you can run up to date software and firewalls and that network appliance in your data center ...
4
votes
1answer
238 views

How big is the risk of hash fixed points/cycles?

It's established wisdom to hash password multiple times with a salt to increase the time it takes per brute force iteration. At the same time (unless the algorithm guarantees otherwise) there's a ...
5
votes
4answers
326 views

provable security and sandboxes

Maybe this can be answered by an answer to a more general question, such as what programs can be proven secure. Can it be (or has it been) formally proven that a sandbox is secure?
25
votes
5answers
2k views

How valuable is secrecy of an algorithm?

On the surface, the inadvisability of security through obscurity is directly at odds with the concept of shared secrets (i.e. "passwords"). Which is to say: if secrecy around passwords is valuable, ...
0
votes
1answer
305 views

Detecting end-state of decryption process with unknown key

Note: this question arises purely from a theoretical interest in security research. Frequently in popular fiction we see white-hat hackers decrypt secret information in a matter of seconds. While ...
1
vote
2answers
487 views

BLP Lattice structure with missing top and bottom levels

I designed a system similar to the above diagram. However There is no (Top Secret, {nuclear,crypto}) and no (Secret,{}) levels. Meaning that there is no top and bottom level. Would it make the BLP ...
1
vote
1answer
164 views

Appilicability of Theoritical Computer Science/Formal methods in Malware research

I would like to know the importance of Theoritical CS/Formal methods in Malware research. Due to the large volume of new malware variants received per day (~50,000 samples/day according to McAfee), ...
14
votes
2answers
1k views

Are there some good papers (or discussions) on using Markov chains or Hidden Markov Models for password auditing/cracking?

As a programmer and language enthusiast I've been very interested in Markov chains for some time. Considering the influence of natural language on password and passphrase selection (by humans of ...
4
votes
1answer
59 views

Are viewable permissions an issue?

Is it, generally, considered to be a security issue if a user in 3-tier application has read-only access to other users' permissions? I.e. Alice can see that Bob has or has not access to some ...
8
votes
7answers
2k views

Definition of Software Security

I'm looking for a theoretical definition of Software Security. And I need to quote some book in an article. Most of the books starts already assuming that the user knows what that is, and they're ...
4
votes
2answers
141 views

Is it correct to consider audits as exclusively “detective” in nature?

I'm studying for the CISSP exam and one of the video lecture points didn't quite make sense to me. The instructor was discussing access control administration areas and began categorizing certain ...
6
votes
4answers
365 views

What is the solution to Schneier's Law?

Schneier's law (which should probably be called Babbage's Law). States that: Anyone, from the most clueless amateur to the best cryptographer, can create an algorithm that he himself can't ...