22,759 reputation
342106
bio website
location Brooklyn, NY
age 34
visits member for 4 years, 2 months
seen 18 hours ago
Good Morning how are you, I'm dr jimbob
I'm interested in things.
I'm not a real dr,
But I am a real jim bob.

Have a PhD in Experimental High-Energy Physics, but left academia in mid-2010 to program professionally.

Mostly program/script in python, django, and jquery these days doing mostly web apps.

Also have experience programming in C, C++, java, haskell, php, and (bash) shell more in the past.

Linux as primary OS since 1999, ubuntu user since 2005 (Hoary).


Jul
22
comment Token-based authentication - what's a good token length?
Meanwhile if your application has say 10 million session tokens in existence, and some botnet attacks your application and manages to do a million requests per second, it would take ~21 days to find one of the 10 million existing session tokens. With a 128-bit session token, it would take more than 10 million times the age of the universe (10 million x 13.7 billion years) to find one of the 10 million session tokens. And with 128-bit, you don't run into collision problems until you have about 2^64 tokens out there which is about 2 billion tokens for every human on earth).
Jul
22
comment Token-based authentication - what's a good token length?
The reason 64-bit is insufficient is that you often don't need to find a specific session token and your system may have millions or billions of session tokens. The chance of session tokens natually colliding among users happens at 2^32~4 billion tokens (see birthday problem ). This could be problematic; and it is not unreasonable to expect very large web applications (or attacked web applications) to eventually generate 4+ billion session tokens.
Jun
30
comment is it easier to eavesdrop on ethernet connection rather than wifi?
This is simply false. WPA and WPA2 (and even WEP, though WEP is broken and should not be used) encrypts the radio transmissions between your laptop/mobile device and the wifi access point.
May
27
comment How to hack into a remote mysql database?
Yes. The MITM tricks the client into believing the server doesn't support SSL. You fix this by upgrading the clients to 5.7.3 or greater, or don't talk to your database over untrusted networks (e.g., use it only as a local application, or a small private network, or over a secure VPN).
May
14
comment Why will Google no longer allow me to end or begin passwords with a space?
My point was from a security perspective, its safer to tell you after inputting a password in a form that will be modified prior to hashing, that "we don't allow passwords greater than 8 characters/with this special character/with unicode characters/with starting/trailing whitespace" while you are setting your password.
Apr
18
comment Do search engines give searcher's IP address to sites that come up in search?
@tim - if the site owner uses google analytics, you get the searched keywords from looking at the analytics. (You won't get them for each individual user straight from google; but if you say cross reference info from the time, user agent, etc with keyword searches you can match them up in your logs.
Apr
3
comment Would the authorities in my college be able to see what websites I accessed through tunneling(SSH)?
ssh -D supports both SOCKS4/SOCKS5 (and man ssh explicitly says it supports SOCKS4 & 5 under the -D option in OpenSSH v6.2 or v6.6). SOCKS5 support has been in OpenSSH since version 3.7 (released Sept 2003). You still have to make sure that you are using SOCKS5 not SOCKS4 (when you configure your browser to connect to the proxy), and that DNS is being done through the tunnel, e.g., in firefox you'll have to enable network.proxy.socks_remote_dns in about:config.
Mar
12
comment Why for some SSL websites browsers show extra info, while for others dont
The benefit of EV certificates is they do fact checking. So if an attacker manages to get a domain like thepaypal.website, the attacker could get regular class-1 SSL certificates for it, but not EV ones as they would not be able to prove they are legal identity paypal.
Mar
12
comment Why for some SSL websites browsers show extra info, while for others dont
-1 - This is wrong. Self-signed certificates will present a scary dialog "Don't trust this connection". The no green box is for regular CA signed class-1 certificates. This validates that the owner of the certificate also controls the domain. (E.g., you bought example.com and can receive emails at admin@example.com). The certificates with the large green boxes are the extended validation certificates which verify that a domain belongs to a real life organization (and the green box displays what organization).
Nov
20
comment Is Certificate-Based Authentication Really Better Than Password Authentication in OpenSSH?
@user10008 - My mistake. I thought "or better" was responding to DigitalChris not to TomLeek. My bad.
Nov
20
comment Is Certificate-Based Authentication Really Better Than Password Authentication in OpenSSH?
@user10008 - Disabling password entry in /etc/shadow is probably not desirable, as typically you may want the ability login to the machine via password when you are physically present (without requiring any of the standard tricks like booting into single user mode or mounting the hard drive from a live cd/usb and editing /etc/shadow ). You would also have to replace the password entry for every user to have the equivalent to PasswordAuthentication no.
Nov
14
comment Truly deniable encryption
What prevents the adversary from cloning the encrypted hard drive first before typing any passwords? (E.g., if a nuke password is given, just copy the clone again);
Nov
8
comment help identifying an IP address from email sent from my gmail account
The only IP address in there is 10.25.30.3 -- an internal IP address used by a google server. (IP address that start with 10. are used for private internal IP addresses ). Change your password and/or enable 2-factor authentication. Don't access your email on public computers that you do not control (and could be using a keyloggers to steal passwords).
Nov
3
comment SSL with GET and POST
@threeFourOneSixOneThree - It is possible for sites to strip sensitive information via javascript. However, by default (at least with all the browsers that I've tested), the referer header includes all HTTP GET query parameters. I've created a link on reddit to whatismyreferer.com (which echos the referer information that websites commonly log). Go to this link with GET parameters at the end like: reddit.com/r/sandboxtest/comments/2l7adf/referer_test/… and you will find the sensitive parts are part of the referer header (even with https).
Oct
30
comment Can anyone be hacked?
I don't agree that everything can be defended effectively from a targeted attack. Yes, you can defend against buffer overflows, SQL injection, etc type attacks. But if some gov't agency with nearly unlimited resources wants to get into your computers -- they can. They may have to bribe people to steal trusted certificates or make "honest" mistakes like heartbleed or just give you access, steal and alter your incoming packages to modify your hardware, break-in and covertly insert hardware keyloggers, threaten someone with access with imprisonment for non-compliance, etc.
Oct
17
comment Is the option to jump to blanks in password fields a security risk?
@CommuSoft - Agreed. Even if you do encrypt your hard drives, any attacker targeting you with physical access can surreptitiously insert a HW keylogger between your keyboard and computer to get your encryption passphrase.
Oct
16
comment Is the option to jump to blanks in password fields a security risk?
@stuXnet The flaw in that scenario is giving her any access to your computer while the password is typed in. A good password will have some ~60+ bits of entropy (to prevent the hash from being cracked offline); knowledge of a few spaces/special characters reduces it by maybe a dozen bits, but out of the realm of an online attack. If she can secretly find the spaces in the password field, she could say accidentally erase/alter it and force you to retype it (and gain more information by watching you type). Or she gets a confederate to come distract you for a second.
Oct
16
comment Is the option to jump to blanks in password fields a security risk?
@stuXnet - Can you think of a scenario where this could gain any info about the password via this attack, where you couldn't recover the complete password via javascript:var inputs=document.getElementsByTagName('input'); for( var i=0; i < inputs.length; i++ ) { if (inputs[i].getAttribute('type') === 'password') alert(inputs[i].value) }? As an analogy, having the last 4 digits of your credit card # on your receipt stored by a business isn't a security risk, as you just handed your full credit card (with your name, the full number, exp date, CVV, etc) to the person who swiped it.
Oct
14
comment What are the odds of an RSA private key collision?
@Brilliand - Yes that was my intention -- apparently I left out the word times. 10^34 * 10^40 != 10^75, but 10^75 isn't some magic spot but roughly where you start to worry; sqrt(N) is easy to remember point for collision attacks for mental math. Doing the math, at 3x10^34 primes, there's a 10^-81 chance of collision (similar to chance of winning powerball jackpot 10 times in a row playing only 1 ticket each time), at 10^74 a 0.03% chance, at 10^75 a 2.6% chance, at 10^75.5 there's a 23% chance, at 10^76 there's a 92.9% chance, and at at 10^77 its 100% chance (off from 1 by 10^-114 %).
Oct
14
comment What are the odds of an RSA private key collision?
@DavidFoerster - Agree colliding fingerprints are a problem, though with SHA-2 signed certificates (the minimum recommendation these days) you have 256-bit which provides 128-bits of security against collision attacks, assuming SHA-2 doesn't have major weaknesses above brute force. This is the reason SHA-1 are being deprecated as it is feasible for a collision attack on a 160-bit SHA-1 key from rogue government-type attackers to fake an intermediate certificate authority via a collision attack)