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SANS ISC: Using Your Password Manager to Monitor Data Leaks - Internet Security | DShield SANS ISC InfoSec Forums


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Using Your Password Manager to Monitor Data Leaks

I wrote this diary while waiting for my flight back to home. Last week, SANSFIRE was held in Washington where I met some ISC handlers. I did not pay too much attention to the security news but I faced an interesting story. Recently, a data leak affected LinkedIn and a friend of mine had a chance to have access to the data (o.a. decrypted passwords). He contacted my and suggested to change my password as soon as possible (as a proof, he sent my password). It was indeed a “valid” one but not my “current” one. More precisely, it was the very first password that I used when a created my LinkedIn account (a long time ago). Interesting… It means that the leaked is not recent.
 
Passwords are a sensitive topic:  don’t play with fire and follow this golden rule: Change them often and don’t re-use them. The “leak” which affected TeamViewer is a good example. I put leak between quotes because it appeared that some of their users were compromised due to password re-use as they stated. To track and analyze this, password managers and dormant accounts can be very useful to track data leaks.
 
Usually, when I receive an invitation to create an account on a website, I accept it and create a unique email account that will NEVER be used somewhere else. I'm using something like: "website-url (at) unused (dot) rootshell (dot) be" or “login_webshop.com". This helps me to track:
  • Spammers:  I can “learn” which site leaked (or sold?) my details to spammers.
  • Data leaks: By crawling paste websites for my dormant email addresses or logins.
Another interesting feature of some password managers (well, the one I’m using includes it), they keep a history of the previous passwords and time stamps (when they have been changed):
Based on this information, I’m able to estimate when the data leak really occurred and if it is really coming from the supposed victim or from another source.  This is a new proof that password managers are mandatory for everybody: they protect you and they contain useful data to analyze security incidents. Stay safe!
 
Xavier Mertens (@xme)
ISC Handler - Freelance Security Consultant
PGP Key
Xme

461 Posts
ISC Handler
I do something similar with my e-mail addresses, e.g., robv AT sans-xxxxxx.domain, where the xxxxxx are six random letters. If I start getting SPAM at an address (e.g., eBay), I can enable, in my e-mail server and on eBay, a new xxxxxx and disable the old xxxxxx. If I need more than one e-mail address for a company, I can create another xxxxxx. And of course it makes it easy to automatically move incoming mail to folders, since the "to" is unique. I have 100's of e-mail addresses out there. I don't know if, for example, Gmail would allow this, but running your own e-mail server makes it pretty easy.

An example problem with this approach came when Microsoft, working with the government, took away my domain (I posted my experience in this forum, in fact, https://isc.sans.edu/forums/diary/Microsoft+NoIP+Takedown/18329). I have since converted to my own .COM (but a lot of my old e-mail addresses are still in use; it's a slow conversion), which I assume is safe from "hostile takeovers."
robv

13 Posts
"I don't know if, for example, Gmail would allow this, but running your own e-mail server makes it pretty easy."

On Gmail or with google apps, you can use +: username+whatever@gmail.com. Unfortunately this is less universal because many sites won't let you use + in the email field because they have really poorly written validation code that won't accept it.
Anonymous
Gmail also lets you sent to a gmail address using a period in the username.... and it just disregards that period.

first.last@gmail.com = firstlast@gmail.com
K-Dee

63 Posts
I agree with it,,..It is necessarry for us to use password manager to protect our accouts..
K-Dee
1 Posts

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