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I will be logging into my bank account and my personal email accounts at work. Its not banned at work, but I just don't want them to save/log a copy of whatever I do with these services. Especially my passwords.

If the service uses a HTTPS connection, will my company be able to track/save/log my passwords, that I use for these services? what about the contents of the pages?

Again, rules in my company don't ban usage of my personal email account or internet banking services, but I just don't want them to know any important information about these. It is okay if they knew that I am using those, but they shouldn't get access to my passwords.

Can I safely use them (knowing my company can't save any of that data) if HTTPS is used?

P.S. I am really not a network guy and I don't know much about how these things work. So please don't give any RTFM replies.

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Like already answered: the network is not the problem. Traces left by your browser (on the computer you're using) are far more likely. Some browsers have explicit settings to enable/disable saving encrypted pages in the offline cache. (Like in Firefox: which defaults to false, which is safe.) – Arjan Feb 1 '10 at 7:13
I am using "private browsing" mode in firefox. I hope that won't save stuff on my system. – senthil Feb 1 '10 at 7:33
No, it's much more likely that your company has monitoring software on your workstation that monitors and records what you do. – BBlake Feb 1 '10 at 15:31
Hey, thanks for all the answers! You've explained a lot of things. Now I understand what is possible and what my company could/couldn't be doing. Judging from what you people have explained, and my company's technical expertise, I can conclude that it is highly unlikely that they will get to know stuff sent over HTTPS. Thanks for all the help! :) I am not a member, so I couldn't upvote a lot of answers even though they deserve it. – senthil Feb 2 '10 at 6:53
up vote 8 down vote accepted

Before answering: If a browser warns you a site is using poor encryption or supplying incorrect identity information, it's important to read the error, understand it, and think hard about whether you want to continue.

Short Answer: Yes.

Long Answer:

If someone in monitoring your connection from another computer (somewhere between you and your bank) and you are using HTTPS, and they are using signed certificates with a suitably strong algorithm, then you are in the clear. (Unless they save the data for years and later read it after the algorithm is broken - but they'd likely be better off breaking into your house and stealing your stuff ;) ).

Chances are if it's your bank then they are using signed certificates with a suitably strong cipher. You can verify this by looking at the SSL information for the page, which should be displayed if you look at the page info click on the Blue or Green name to the left the address bar with Firefox 3.5, or lick on the lock to the right in the address bar in IE8. Firefox will also display the encryption algorithm used if you select More Information after clicking on the coloured area.

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okay. Take hotmail for example. If I select "use enhanced security" when logging in, it switches to a HTTPS connection. in Firefox, the address bar thing is green, and from what is displayed there, i think it is pretty secure. Taking this as an example, for practical purposes, it is perfectly okay to use websites with this kind of HTTPS connection, knowing that no one (atleast in the next couple of months) can decrypt the information. Am I correct? – senthil Feb 1 '10 at 8:07
I would think so. I'd be surprised if a network administrator were to gain access to your bank account using network traffic alone when you use HTTPS. With that said, there are other ways you could be vulnerable even when using a secure connection, and you should follow your bank's instructions on how to use their site - such as always logging out after finishing (as opposed to closing the window) and not browsing other sites while banking. Always use an up-to-date browser, and make sure the computer your using is trusted with anti-virus software. – Tyler Szabo Feb 2 '10 at 8:15

No, not neccessarily. Your company may send your connection through a proxy that acts as a man-in-the-middle. That is: All HTTPS traffic goes from your machine to the proxy, is decrypted there, analyzed, encrypted and sent to the server. Your machine will not use the security certificate from the server, but instead the proxy will generate one for the given website and send that to you, so you really have two HTTPS Connections: From you to the proxy and from the proxy to the server.

In other to make that happen, the company needs to have a certificate server to generate a certificate. Normally the browser would object here and complain that the certificate authority is not trusted, but of course that can be overridden through group policies and the like.

This is not necessarily foul play by the employer though, as this can be part of an anti-virus concept or due to legal reasons.

In your browser, look at the certificate. Especially, look at the certificate authority. If the certificate is issued by a "real" CA like Thawte, VeriSign etc., then that would mean that you're using the one from the server and you should be safe. However, if it is issued by something like "YourCompany-AV" or the like, then you have a man-in-the-middle proxy.

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I think may should be emphasised here. Normal proxies do not create certificates on the fly, and do not decrypt HTTPS traffic (but support the CONNECT method). – Arjan Feb 1 '10 at 14:32
...but then again: the question asker is concerned, so maybe it's just as well to mention all possibilities. (And maybe there's more companies with such proxy than I could imagine? +1 after all!) – Arjan Feb 1 '10 at 15:01
True, normally Proxies just pass through HTTPS traffic as they can't do anything with it, and I do not know if HTTPS-Inspection is on the rise, but I've seen it happen so I just thought I point out the possibility. – Michael Stum Feb 1 '10 at 15:26
I don't know how common the practice is, but my employer does do this. AFAIK it's to make sure we're not sending proprietary data out of the network over SSL. – Dan Neely Feb 1 '10 at 16:14
@senthil The point of HTTPS is to encrypt traffic and to identify the participants. Anyone who controls the line can theoretically be a man in the middle (hence it is even called man-in-the-middle attack) but unlike unencrypted HTTP, this will not stay undetected. As said, check the certificate and who issued it. There is no way usually to fake a certificate (There was a bug in some Debian Linux versions that made it possible to fake certs, but that was so far an isolated incident). – Michael Stum Feb 3 '10 at 1:07

Generally speaking, you are safe.Because the when you visit the website of bank through https connection, all data like user name and password are encrypted, it is hard to decrypt it in a very short time, unless they know the encryption algorithm very well. However, there's other attack such as key logger,man in the middle will work if they are knowledgeable.Always pay attention to the environment before you enter the sensitive information.

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man in the middle will work if they are knowledgeable -- with HTTPS? – Arjan Feb 1 '10 at 12:31

If you are using a company owned machine and have agreed to the companies policies there may be issues at hand that are specific to your company. Without knowing any further details I'd say you should be secure, but I have to balance that with a caveat. Technically it is possible, but if you lead a "normal" life there are plenty of things that you face every day that present a much more likely risk to your personal data than the scenario that you are asking about.

Some basic things to be aware of. The company could still be aware of which sites you are visiting and for how long. The data may be encrypted, but it still has to be routed so the address that the data is going from and to is exposed.

The advice in other answers about taking advantage of any security features of your browser is good. I'll add that you should take a moment to review your companies policies that relate to personal data on work machines.

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Hi, as I mentioned, I am not worried about them knowing what sites I visit and for how long, as long as they don't know what I type in the text fields. And I am absolutely sure they don't have key loggers. – senthil Feb 1 '10 at 9:15

Banks generally use a 128 bit encryption, or higher. Check the properties of their SSL cert, or even ask one of their technical support to find out what it is. If it's under 128 I would suggest not using it. But if it is 128 or over, you should be fine. Unless someone on the network with Ettercap, Wireshark, Shijack and a massive chip on their shoulder has something against you. If you're that worried about it, however, then simply don't use net banking at work. Then again, what's to stop someone cracking your computer at home to get your banking information? You're probably safer at work. My managers could barely check my browser history - I'd like to see them crack a SHA1-RSA encryption provided by a SSL cert.

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ROFLOL.. I didn't stop laughing for 2 mins after I read your last line :D – senthil Feb 1 '10 at 11:36
Did you just chain a bunch of tangentally-related words together? – insta Oct 17 '11 at 16:19

Effectively you are safe simply because generally network admins have better things to do. Technically, no, your data is not safe. You didn't say what field you were in, but call center work for example will have systems that are extremely monitored. Data encryption doesn't matter if keystrokes are being logged and the screen captured as a part of normal operation. If you are worried that admins may be inclined to look at your bank account information, then DO NOT use your work computer for banking.

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It is possible to save packets and break rsa encryption later on, though since the Internet is based on packet switching it is unlikely that any attacker would have enough substance to reconstitute TCP packets.

Everything and anything is possible.

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You can bruteforce even 1024-bit RSA for months with hundreds of computers (,132184-pg,1/article.html), and 2048-bit isn't so rare nowadays. – whitequark Feb 1 '10 at 7:36
OK I dont care if its 399 millennia, its still possible. – Recursion Feb 1 '10 at 8:33
However, who will spend all this computing power to break a banking SSL connection, unless there is something very suspicious about this user ? As said before, if you're a normal worker, and you're not doing anything illegal already, you should not worry, unless your boss has very good reason to spy on you. He, it would be easier to hide half a dozen of web cams to spy on your keystrokes than it would be to decrypt your SSL traffic. – jfmessier Feb 1 '10 at 13:17
OK and again, the OP asked if it were possible, not if its probable. Keep down voting please. – Recursion Feb 1 '10 at 22:05
. nice of you to take time to answer :). I guess practicality was implied in my question. Why would I care if someone found out my bank account details 399,000 years after I am dead? :P – senthil Feb 2 '10 at 6:59

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