{"id":4430,"date":"2018-01-26T08:07:45","date_gmt":"2018-01-26T02:37:45","guid":{"rendered":"https:\/\/qadit.com\/blog\/?p=4430"},"modified":"2018-01-26T08:07:45","modified_gmt":"2018-01-26T02:37:45","slug":"whatsapp-vulnerability","status":"publish","type":"post","link":"https:\/\/qadit.com\/blog\/whatsapp-vulnerability\/","title":{"rendered":"WhatsApp Vulnerability"},"content":{"rendered":"<div>\n<div class=\"comment by-maqp\" id=\"c6768935\">\n<p class=\"commentcredit\"><span class=\"commenter\">maqp<\/span> \u2022 <a href=\"https:\/\/www.schneier.com\/blog\/archives\/2018\/01\/whatsapp_vulner.html#c6768935\">January 25, 2018  5:50 PM<\/a>\n<\/p>\n<p>@Afrin, (and Moxie)<\/p>\n<p>&#8220;If someone hacks the WhatsApp server, they can obviously alter the group membership.&#8221;<\/p>\n<p>This &#8220;duh, obviously the proprietary app using Signal protocol has a problem where Signal spec differs from the original open source library in a way that gives the server ability to add contacts that can eavesdrop on communication&#8221; is so obvious. How could I have assumed anything different after Moxie said WhatsApp uses same protocol as Signal.<\/p>\n<p>&#8220;All group members will see that the attacker has joined. There is no way to suppress this message.&#8221;<\/p>\n<p>Moxie misses the fact that some group chats consist of communities where not everyone knows each other. While such groups do have different expectation of privacy for messages, that&#8217;s no reason not to have security from nation states. And it&#8217;s not impossible to join it without anyone noticing, especially since attacker can forge to each user a message about who added them. Nobody&#8217;s going to tell everyone to be quiet and interrogate the new buddy of buddy. Very few actually care about what they share in group if they don&#8217;t know them IRL. It&#8217;s easy not to think about those contacts.<\/p>\n<p>&#8220;I think it would be better if the server didn&#8217;t have metadata visibility into group membership, but that&#8217;s a largely unsolved problem&#8221;<\/p>\n<p>Metadata about who&#8217;s in the group isn&#8217;t the problem here. Ability to add members to group is.<\/p>\n<p>&#8220;In contrast, Telegram does no encryption at all for group messages&#8221;<\/p>\n<p>True. But this is also whataboutism. We should not tolerate Durov&#8217;s &#8220;Signal is funded by US governemnt&#8221; accusations, and we shouldn&#8217;t accept pointing fingers from Moxie&#8217;s side when discussing this issue. This was a screw-up from WhatsApp developers, not Moxie, and I don&#8217;t understand why he would stand behind their backs.<\/p>\n<p>&#8220;There&#8217;s no way to publish an academic paper about that, though, because there&#8217;s no attack to describe, because there&#8217;s no encryption to begin with.&#8221;<\/p>\n<p>It was only this week Tinder made the headlines for not using any encryption at all. Also, there was no attack to describe in Signal yet somehow they managed to publish <a href=\"https:\/\/eprint.iacr.org\/2016\/1013.pdf\" rel=\"nofollow\">a formal Signal audit<\/a>. It probably didn&#8217;t make the headlines back in 2016 but is even today extremely valuable proof of security. Audit that makes note of Telegram&#8217;s crappy TLS group messaging would not only convince some users, it could also be used as a source in debates, and there&#8217;s a chance it could make headlines. One big issue with Telegram currently is it&#8217;s outdated evaluations. It&#8217;s not clear to what protocol versions audits apply to or what attacks, like the infamous <a href=\"https:\/\/www.alexrad.me\/discourse\/a-264-attack-on-telegram-and-why-a-super-villain-doesnt-need-it-to-read-your-telegram-chats.html\" rel=\"nofollow\">64-bit precomputation MITM attack<\/a>, still apply to the client.<\/p>\n<p>&#8220;don&#8217;t build security into your products, because that makes you a target for researchers, even if you make the right decisions, and regardless of whether their research is practically important or not&#8221;<\/p>\n<p>There&#8217;s nothing overly impractical about this attack. We consider Telegram&#8217;s encryption broken when all it lacks semantic security (IND-CCA). All this means is you can edit ciphertext without changing to what it decrypts into. That&#8217;s no different from messing with imaginary ECC bundled into ciphertext. So, why don&#8217;t we consider a protocol (implementation) broken when there&#8217;s a good chance several end-to-end encrypted messages might leak to adversary when they are able to join the conversation.<\/p>\n<p>It&#8217;s true it&#8217;s hard to write stories about Telegram that raise eyebrows, especially with media fixated on Durov as a celebrity. But if enough experts agree on how Durov&#8217;s claims about <a href=\"http:\/\/telegra.ph\/Why-Isnt-Telegram-End-to-End-Encrypted-by-Default-08-14\" rel=\"nofollow\">distributed cross-jurisdictional encrypted cloud storage<\/a> are full of shit, it might change things.<\/p>\n<p>&#8220;It&#8217;s much more effective to be Telegram: just leave cryptography out of everything, except for your marketing.&#8221;<\/p>\n<p>This sums my feelings about Telegram exactly. Everything they do could work on Signal protocol. But it&#8217;s too easy to beat the competition for ignorant user-base with invisible insecurity that enables much faster message delivery and feature development.<\/p>\n<\/div>\n<\/div>\n<p><b>Read the Full Article here: <a href=\"https:\/\/www.schneier.com\/blog\/\">&gt;Schneier on Security: Cybercrime Paper<\/a><\/b><\/p>\n","protected":false},"excerpt":{"rendered":"<p>maqp \u2022 January 25, 2018 5:50 PM @Afrin, (and Moxie) &#8220;If someone hacks the WhatsApp server, they can obviously alter the group membership.&#8221; This &#8220;duh, obviously the proprietary app using Signal protocol has a problem where Signal spec differs from the original open source library in a way that gives the server ability to add &hellip; <\/p>\n<p class=\"link-more\"><a href=\"https:\/\/qadit.com\/blog\/whatsapp-vulnerability\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;WhatsApp Vulnerability&#8221;<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","enabled":false},"version":2}},"categories":[12],"tags":[293],"class_list":["post-4430","post","type-post","status-publish","format-standard","hentry","category-itsec","tag-wonder-information"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p9AH7Q-19s","_links":{"self":[{"href":"https:\/\/qadit.com\/blog\/wp-json\/wp\/v2\/posts\/4430","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/qadit.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/qadit.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/qadit.com\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/qadit.com\/blog\/wp-json\/wp\/v2\/comments?post=4430"}],"version-history":[{"count":1,"href":"https:\/\/qadit.com\/blog\/wp-json\/wp\/v2\/posts\/4430\/revisions"}],"predecessor-version":[{"id":4431,"href":"https:\/\/qadit.com\/blog\/wp-json\/wp\/v2\/posts\/4430\/revisions\/4431"}],"wp:attachment":[{"href":"https:\/\/qadit.com\/blog\/wp-json\/wp\/v2\/media?parent=4430"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/qadit.com\/blog\/wp-json\/wp\/v2\/categories?post=4430"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/qadit.com\/blog\/wp-json\/wp\/v2\/tags?post=4430"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}