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154

It's not just about you. By forcing users to use TLS, they're creating a more secure environment for everyone. Without TLS being strictly enforced, users are susceptible to attacks such as sslstrip. Essentially, making unencrypted connections an option leads to the possibility of attackers forcing users into unencrypted connections. But that's not all. ...


78

Let me rephrase your question with a few extra details, which are implicit but maybe not obvious to everybody: "Isn't Google being Evil by providing me with a free email service and gigabytes of storage and forcing me into a secure connection when I access that service which they have generously granted to me and that nobody forces me to use even if I don't ...


68

The issue you're dealing with, here, is that if you decide not to encrypt a connection, you're making assumptions regarding the sensitivity of the data that goes over that connection. Unfortunately, it is impossible to properly make that assumption because: You might not have fully understood all the implication of the data (for instance, if Twitter ...


59

It means much more than just new certificates (or rather, new key pairs) for every affected server. It also means: Patching affected systems to OpenSSL 1.0.1g Revocation of the old keypairs that were just superseded Changing all passwords Invalidating all session keys and cookies Evaluating the actual content handled by the vulnerable servers that could ...


55

As a matter of fact, yes, clients are vulnerable. So far the attention has been focused on servers as they are much more open to exploitation. (Almost) everyone can connect to a public HTTP/SMTP/... server. This blog describes how the bug actually works (it mentions dtls_process_heartbeat(), but tls_process_heartbeat() is affected in the same way). This ...


53

Encryption is not just about preventing eavesdroppers from reading data, it also prevents them from changing it. Flipping images on webpages upside down is an amusing prank to play on housemates but a malicious person could inject ads, or harmful code (Java, Javascript, Flash etc.) into your webpages without you realizing it. ...


32

You have covered the main ones. In short: it's very hard, if not impossible, to effectively block a site you want. You can make it hard by using the techniques you've mentioned: blocking IPs, redirecting DNS, blocking HTTP requests to certain sites / containing certain keywords. These methods are thwartable by proxies (in the case of deep packet ...


32

I am not aware of any definitive, "official" answer on this subject, but this seems to be part of an attempt at genericity and coherence. In the SSL/TLS standard, all messages follow regular encoding rules, using a specific presentation language. No part of the protocol "infers" length from the record length. One enlightening detail is the ClientKeyExchange ...


29

There are a number of reasons not to use SSL, none of which being a good reason in itself, but cumulatively they can explain a lot of things. The main reason not to use SSL is an effect of the strongest force in the Universe, i.e. laziness. However easy setting up SSL is, not setting it up will still be easier. This alone explains why so many sites still ...


27

In addition to the other good answers I would add that HTTPS ensures that when I think I'm reading bbc.com, I really am reading the content provided by bbc.com, not a hostile third-party who wants to fool me. Some news sites still present facts. People make decisions based on those facts -- decisions that have real-world consequences.


22

For TLS with the purpose of liveliness (keep-alive) checks, there's no reason to: Encode a payload size field in the heartbeat request/response header (the length of the payload comes from the record layer rrec.length in OpenSSL code -- you just have to subtract off the fixed HB header size from this), Allow HBs to be variable size -- a small HB size (in ...


21

I wrote a Metasploit module to test this, its currently being reviewed, but should hit the master branch relatively soon. The first version is merged into the master branch at this point. https://github.com/rapid7/metasploit-framework/blob/38a2614fbee1851252462c858057738c06a9f2ab/modules/auxiliary/server/openssl_heartbeat_client_memory.rb Unlike the ...


21

When data is exchanged over the Internet, it hops from router to router, starting with the source (your desktop computer) and ending with the destination (the authentication server to which you are sending the password). All the routers, by definition, "see" the data. Moreover, all machines which are directly plugged with the link between any two routers can ...


14

In fact, no, Google is not evil with this, not at all. The first important thing about this is that the use of secure connection is not a user preference or some personalized setting. Some people might find this confusing because they are familiar with a system only from the position of an end-user. Being a software developer myself, I can tell you that ...


14

There are no technical reasons for such a limit, it's purely licensing (i.e. revenue, and maintaining market segmentation). There are some considerations relating to the secure transfer of the key between systems when you do this, but this is easily addressed. If you violate the license or terms of an agreement you risk (at least) getting your certificate ...


14

The heartbeat serves two purposes: to make some link-level activity (to avoid closure by zealous firewalls) and to make sure that the peer is still alive. If you want to do both with empty fragments, then you need some convention between client and server, so that when you send an empty fragment, the peer responds with an empty fragment. This has potential ...


13

If you look into the RFC6520 (heartbeat extension) there is a padding after the payload. So the length is required to know where the payload ends and the padding starts. Apart from that I find the design overengineered: the both reasons for this extension seem to be to make PMTU possible (by using messages of different size) and by heaving heartbeat to know ...


11

One reason in general I would like to add to the above answers is that even though you might not be doing something highly illegal in a western country, you should not assume that the government is not interested in what you read. Reading the following might put you on a list: Classified, documents leaked by whistle-blowers that are technically illegal A ...


11

"Efficiency" depends on your goals. An important point to be made is that all blocking techniques can be circumvented, at a price. For instance, an individual can use a satellite phone to get connectivity which cannot be blocked by his country, save by direct physical intervention of armed forces. But using such systems is quite expensive. Countries which ...


10

As a general rule, it's good policy to strongly encrypt all data travelling across public networks. The reason is that if only "sensitive" data is encrypted, it's very easy for eavesdroppers to target potentially useful data simply by looking for anything that's encrypted. However, if everything is encrypted by default then they have no idea what ...


10

Evil for forcing you to use a secure connection? No, I don't think it's evil. It protects the community at large with no downside to you as an individual. I think its only evil if they're forcing you to use SSL/TLS, then failing to use forward secrecy, thus giving you and everyone else using the service a false sense of security. Without forward secrecy, ...


10

The 64k block that gets returned is selected effectively at random, which seems like it would make it hard to find worthwhile data. However, there are two factors that significantly increase the threat: First, the attack won't return memory that was allocated during program start-up. This means the area occupied by boring things like program code won't ...


9

You can try StartSSL who will issue you a free SSL certificate that will be trusted. I use one of their certificates on my blog and yes, it really is free. Their site doesn't have the best user interface admittedly, but if you can live with that, this sounds like your best option.


9

You are confusing RSA, a family of cryptosystems that relies on the difficulty of factoring products of large prime numbers, with RSA Security LLC, a company which sells security-related products. RSA and RSA are both called RSA after Messrs R, S and A, who both invented the RSA cryptosystem and founded the RSA company. The company was founded in part to ...


9

You are correct. Some ways for the site to decrease that attack vector would be to... Use an HSTS header to prevent any data from being sent to the site in plaintext. Advertise only the HTTPS URL and do not allow any plaintext connections. This will ensure most bookmarks use encryption. The point being that sites should force SSL from the beginning, ...


8

In addition to what Thomas said, straightforward practical reasons: for smaller services, cheap hosting which doesn't give you direct access to configure your server with certs (or indeed provide the unique IP address you'd need to do SSL up until the day we can really rely on SNI) you need to include third-party content (iframes, scripts etc) which isn't ...


8

I think that really depends on the extent of definition of "sensitive data." Passwords and credit card numbers is certainly one, but perhaps looking up on WebMD info about a rash, while a generally public info, may be something that you're sensitive about, and don't want employer or your ISP to know (employers' rights and use of work equipment arguments ...


8

It's sad that people's first reaction is to defend Google by using the "you don't HAVE to use it" fallacy. As for transaction of money, don't you think your own personal information which they sell to advertisers has monitory value? Google isn't free, it still requires a payment which most people don't even realize they are making. Now, to answer the ...


8

Yes, and this is exactly what the SSL Strip attack did, while using the unsecure HTTP connection it transparently turned all HTTPS links in to HTTP links and proxied the connection, if you did not notice that you where not on a HTTPS connection you could easily send confidential data over a unsecure connection. As a web site admin you can combat this by ...


8

A one time pad offers information theoretic security. This essentially means that the one time pad cannot be broken even if the adversary has unlimited computing power. This is because XOR-ing any data against a truly random key will guarantee that the output be random as well because you are simply flipping bits.



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