Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [nsa]

The National Security Agency (NSA) is the central producer and manager of signals intelligence for the United States Government.

8
votes
1answer
1k views

Why does BCRYPT_RNG_DUAL_EC_ALGORITHM get removed from CNG API on Windows 10?

On article at => Microsoft Docs CNG Algorithm Identifiers I notice that BCRYPT_RNG_DUAL_EC_ALGORITHM is now removed since Windows 10. Beginning with Windows ...
4
votes
0answers
92 views

aside from DES has the NSA ever strengthened algorithms?

When DES was originally developed, the NSA changed the s-boxes. For decades people thought that their changes introduced a backdoor but then it was discovered that their changes actually strengthened ...
3
votes
0answers
457 views

What are the relations between cryptanalysis of block ciphers such as AES and Kendall's tau coefficient?

Studying AES on Wikipedia, I noticed a statement regarding some ongoing studies on the use of Kendall's Tau coefficient in cryptanalysis: According to the Snowden documents, the NSA is doing ...
26
votes
3answers
5k views

How Far Ahead of Academia Are Government Agencies? [closed]

This is a soft question regarding comparisons between government security services (eg, NSA or GCHQ) and open-source research (e.g., academia). Hopefully it's on-topic for this site! In essence, my ...
0
votes
1answer
583 views

Cryptographic algorithms compromised and alternatives?

After Edward Snowden's release of top secret information we have seen clues that the NIST certified crypto-algorithms like AES might be compromised. Although not as fast as AES, we prefer Twofish ...
-2
votes
1answer
228 views

I can divide a very large integer - did I discover anything?

So I was sitting on an algorithm I thought up at school, and just decided to implement it. And it worked for what I wanted - but I don't know what this is worth. I broke apart a 2048 private key for ...
2
votes
0answers
59 views

If Kerckhoffs's principle is correct why does the NSA not publish their Suite A ciphers? [duplicate]

The Wikipedia article offers little insight. To quote the page: the decision to keep them secret is in keeping with a layered security posture How should we (the cryptographic community) ...
2
votes
2answers
740 views

Keyless integrity checking with SHA-256

Currently a program is loading some files from an untrustworthy source (e.g. a CDN) which could have been tampered with. It has a known SHA-256 hash of the file stored locally, then it downloads the ...
2
votes
1answer
2k views

RSA vs ECDSA/ECDH

So we've been using RSA for a while now. I wonder, is it still secure? I'm wondering whether surveillance agencies can at this point read traffic encrypted with say, TLS_ECDH_RSA_WITH_AES_128_GCM? ...
4
votes
1answer
160 views

State level “Weak Diffie-Hellman” working for SRP too?

I've read about the "Weak Diffie-Hellman" attack (paper, website), where a resourceful entity like a state can pre-compute values for known primes to aid solving the discrete logarithm problem for ...
9
votes
1answer
212 views

What was the NSA's reasoning for making their bitwise combination functions in SHA-1 the way they did?

I know that these functions are there to actually make the program work. What I want to know is why they made the functions one way but not another. For example, why did they pick F1(B, C, D) = (B &...
-1
votes
1answer
371 views

HMAC-Ripemd-160 in TrueCrypt

I'm wondering if it is still secure. I know TrueCrypt closed its doors but I continue using it because the cryptoaudit didn't find any huge bugs or security issues in TrueCrypt. But I have a bad ...
2
votes
2answers
420 views

Is it possible to calculate the 'skeleton key' for DUAL_EC_DRBG? What would it take?

According to Bruce Schneier the constants used in the spec of DUAL_EC_DRBG may be related to a secret set of numbers, that could function as a master key for ...
6
votes
1answer
667 views

What could “look for the constants that you might find in RC6” mean?

In this presentation at the 30c3 (long but extremely interesting and well-documented), Jacob Appelbaum gave this verbal advice (circa 43'30"): look for the constants that you might find in RC6 I'm ...
0
votes
1answer
218 views

What is the difference between exhaustive search and factorization in relationship to determining a key?

It seems to me an exhaustive search would simply try to use all the possible bit combinations of a key, while factorization is some mathematical formula for determining the key? When discussing the ...
2
votes
2answers
366 views

Solid summary of what encryption remains strong after recent events [closed]

Following the recent government hacking (and subsequent news and fallout), I'm wondering what crypto-systems remain strong (and why) and what crypto-systems were exploited too heavily to be reliable. ...
1
vote
0answers
254 views

PGP encryption options

I recently began using PGP desktop and found several options for my encryption capabilities. Which of these (AES, Cast, Triple DES, TwoFish, IDEA) is the most recent, firstly, secondly may the NSA not ...
9
votes
2answers
3k views

Does Microsoft use Dual_EC_DRBG by default?

So, as we all know, Dual_EC_DRBG contains an NSA back door. At this point, there is no reason to call it a "potential" or even an "alleged" back door; the presence is obvious even to the NY Times. As ...
35
votes
1answer
29k views

Explaining weakness of Dual EC DRBG to wider audience?

I have an audience of senior (non-technical) executives and senior technical people who are taking the backdoor in Dual_EC_DRBG and considering it as a weakness of Elliptic curves in general. I can ...
5
votes
2answers
318 views

Fast post-processing for broken RDRAND

Let's assume that the Intel RDRAND instruction does not return fully random numbers, e.g. because it has been engineered with a backdoor for the NSA. If the Intel RDRAND instruction is used directly ...
5
votes
1answer
3k views

Who uses the RSA BSAFE library? [duplicate]

Who uses RSA's BSAFE library? Does anyone know what products use it, or have any statistics on how many end users use something that is built on BSAFE? Background: BSAFE is one of the oldest ...
2
votes
1answer
630 views

Hide a weakness in ECC by choosing the prime or one of the curve coefficients

Suppose you are given a value $c$. Can you find a prime $p$ and an integer $b$ such that the elliptic curve $$E: y^2 \equiv x^3 -3x + b \pmod p$$ is cryptographically weak? You need to choose $p,b$...
26
votes
5answers
5k views

Could RDRAND (Intel) compromise entropy?

I was recently discussing the issue of RDRAND in Intel chips and the whole issue about how NSA could potentially be influencing Intel to weaken or create backdoors in their design. This petition was ...
140
votes
4answers
44k views

Should we trust the NIST-recommended ECC parameters?

Recent articles in the media, based upon Snowden documents, have suggested that the NSA has actively tried to enable surveillance by embedding weaknesses in commercially-deployed technology -- ...
15
votes
1answer
1k views

What NIST protocol was allegedly backdoored by NSA in 2006?

From a recent NY Times article: Cryptographers have long suspected that the agency planted vulnerabilities in a standard adopted in 2006 by the National Institute of Standards and Technology ...
46
votes
5answers
16k views

Who uses Dual_EC_DRBG?

Recent news articles have suggested that the NSA may be involved in trying to influence the cryptography in public standards or commercially deployed software, to enable the NSA to decrypt the ...
20
votes
3answers
14k views

Why is the P-521 elliptic curve not in Suite B if AES-256 is?

In the NSA's document, "The Case for Elliptic Curve Cryptography" (archived), we have ...
8
votes
1answer
755 views

What does NSA mean by 'Analyzable'?

Recently NSA published two new algorithms, Simon and Speck. In the abstract they say The aim of SIMON and SPECK is to fill the need for secure, flexible, and analyzable lightweight block ciphers. ...