{"id":207434,"date":"2017-04-19T14:45:12","date_gmt":"2017-04-19T12:45:12","guid":{"rendered":"http:\/\/mybroadband.co.za\/news\/?p=207434"},"modified":"2017-04-19T14:46:31","modified_gmt":"2017-04-19T12:46:31","slug":"punycode-url-attack-can-trick-chrome-and-firefox-users","status":"publish","type":"post","link":"https:\/\/mybroadband.co.za\/news\/security\/207434-punycode-url-attack-can-trick-chrome-and-firefox-users.html","title":{"rendered":"Punycode URL attack can trick Chrome and Firefox users"},"content":{"rendered":"

The way Chrome, Firefox, and Opera handle special characters in URLs may be exploited to set up a website with a URL that looks exactly the same as\u00a0a reputable website, Bleeping Computer reported<\/a><\/strong>.<\/p>\n

Called an IDN homograph attack, the vulnerability exists in browsers which\u00a0elect to render non-Latin characters that resemble Latin characters in the URL bar.<\/p>\n

This is possible due to Internationalised Domain Names which allow the use of non-ASCII characters.<\/p>\n

A domain like \u00e5\u00e4\u00f6.se is\u00a0therefore legal, so long as the top-level domain (in this case, Sweden\u2019s .se) allows it.<\/p>\n

The Internet Corporation for Assigned Names and Numbers allows the use of non-ASCII characters in URLs, but acknowledged it may lead to confusion.<\/p>\n

It voted to use a standard called Punycode instead of Unicode, which allows browsers to print non-Latin characters using the Latin alphabet. For example, the Cyrillic \u201c\u0430\u201d is xn\u201380a.<\/p>\n

Browsers developed protections against obvious attacks which\u00a0mix Latin and non-Latin alphabets to create URLs that look legitimate by displaying the Punycode rather than the characters.<\/p>\n

If someone spoofed Apple\u2019s website by changing the \u201ca\u201d to the Cyrillic \u201c\u0430\u201d to give \u0430pple.com, browsers would instead show xn\u2013pple\u201343d.com in the URL bar.<\/p>\n

The exploit<\/h3>\n

However, when characters from only one alphabet are used, Chrome, Firefox, and Opera do not show the Punycode.<\/p>\n

According to the report, Edge, Internet Explorer, Safari, Vivaldi, and Brave browsers display the Punycode by default and are not vulnerable.<\/p>\n

Security researcher Xudong Zheng<\/a><\/strong> demonstrated the exploit by setting up a fake website which\u00a0looks like the real thing.<\/p>\n

Zheng used \u0430\u0440\u0440\u04cf\u0435.com, which may look like the real apple.com, but the URL is in Cyrillic script and becomes xn\u201380ak6aa92e.com in Punycode.<\/p>\n

Chrome has fixed the issue in version 59 of the browser and rolled out a patch to Chrome 58.<\/p>\n

Firefox is\u00a0yet to address the issue.<\/p>\n

Zheng said Firefox users can set the browser to always display non-Latin URLs in Punycode by going to “about:config” and setting “network.IDN_show_punycode” to true.<\/p>\n

\"Zheng<\/a><\/p>\n

Now read: Over 14,000 Let\u2019s Encrypt SSL certificates issued to \u201cPayPal phishing sites\u201d<\/a><\/h3>\n","protected":false},"excerpt":{"rendered":"

The way Chrome, Firefox, and Opera handle special characters in URLs can potentially be exploited.<\/p>\n","protected":false},"author":15,"featured_media":162888,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[27],"tags":[35085,1567,35224,981,42668,19484,983,207,42664,985,29740,42666],"class_list":["post-207434","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-security","tag-brave","tag-chrome","tag-edge-browser","tag-firefox","tag-internationalised-domain-name-idn","tag-internet-corporation-for-assigned-names-and-numbers-icann","tag-internet-explorer","tag-opera","tag-punycode","tag-safari","tag-vivaldi","tag-zheng"],"_links":{"self":[{"href":"https:\/\/mybroadband.co.za\/news\/wp-json\/wp\/v2\/posts\/207434"}],"collection":[{"href":"https:\/\/mybroadband.co.za\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mybroadband.co.za\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mybroadband.co.za\/news\/wp-json\/wp\/v2\/users\/15"}],"replies":[{"embeddable":true,"href":"https:\/\/mybroadband.co.za\/news\/wp-json\/wp\/v2\/comments?post=207434"}],"version-history":[{"count":1,"href":"https:\/\/mybroadband.co.za\/news\/wp-json\/wp\/v2\/posts\/207434\/revisions"}],"predecessor-version":[{"id":207550,"href":"https:\/\/mybroadband.co.za\/news\/wp-json\/wp\/v2\/posts\/207434\/revisions\/207550"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/mybroadband.co.za\/news\/wp-json\/wp\/v2\/media\/162888"}],"wp:attachment":[{"href":"https:\/\/mybroadband.co.za\/news\/wp-json\/wp\/v2\/media?parent=207434"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mybroadband.co.za\/news\/wp-json\/wp\/v2\/categories?post=207434"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mybroadband.co.za\/news\/wp-json\/wp\/v2\/tags?post=207434"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}