Facebook Old Generated URLs Still Vulnerable to Open Redirect Attacks & A New Open Redirect Web Security Bugs

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Facebook Old Generated URLs Still Vulnerable to Open Redirect Attacks & A New Open Redirect Web Security Bugs




Domain:
http://www.facebook.com



“Facebook is an online social networking service headquartered in Menlo Park, California. Its website was launched on February 4, 2004, by Mark Zuckerberg with his college roommates and fellow Harvard University students Eduardo Saverin, Andrew McCollum, Dustin Moskovitz and Chris Hughes. The founders had initially limited the website’s membership to Harvard students, but later expanded it to colleges in the Boston area, the Ivy League, and Stanford University. It gradually added support for students at various other universities and later to high-school students. Since 2006, anyone who is at least 13 years old is allowed to become a registered user of the website, though the age requirement may be higher depending on applicable local laws. Its name comes from a colloquialism for the directory given to it by American universities students.” (Wikipedia)



“Facebook had over 1.44 billion monthly active users as of March 2015.Because of the large volume of data users submit to the service, Facebook has come under scrutiny for their privacy policies. Facebook, Inc. held its initial public offering in February 2012 and began selling stock to the public three months later, reaching an original peak market capitalization of $104 billion. As of February 2015 Facebook reached a market capitalization of $212 Billion.” (Wikipedia)





Discover:
Wang Jing, Division of Mathematical Sciences (MAS), School of Physical and Mathematical Sciences (SPMS), Nanyang Technological University (NTU), Singapore. (@justqdjing)
http://www.tetraph.com/wangjing/

 



(1) General Vulnerabilities Description:

(1.1) Two Facebook vulnerabilities are introduced in this article.

Facebook has a computer cyber security bug problem. It can be exploited by Open Redirect attacks. This could allow a user to create a specially crafted URL, that if clicked, would redirect a victim from the intended legitimate web site to an arbitrary web site of the attacker’s choosing. Such attacks are useful as the crafted URL initially appear to be a web page of a trusted site. This could be leveraged to direct an unsuspecting user to a web page containing attacks that target client side software such as a web browser or document rendering programs.


Since Facebook is trusted by large numbers of other websites. Those vulnerabilities can be used to do “Covert Redirect” to other websites such as Amazon, eBay, Go-daddy, Yahoo, 163, Mail.ru etc.

 

(1.1.1)

One Facebook Open Redirect vulnerability was reported to Facebook. Facebook adopted a new mechanism to patch it. Though the reported URL redirection vulnerabilities are patched. However, all old generated URLs are still vulnerable to the attacks. Section (2) gives detail of it.

The reason may be related to Facebook’s third-party interaction system or database management system or both. Another reason may be related to Facebook’s design for different kind of browsers.

 

(1.1.2) Another new Open Redirect vulnerability related to Facebook is introduced, too. For reference, please read section (3).

The vulnerabilities can be attacked without user login. Tests were performed on IE (9.0) of Windows 8, Firefox (24.0) & Google Chromium 30.0.1599.114 ubuntu0.14.04.1.1064 (64-bit) of Ubuntu (12.10),Safari 6.1.6 of Mac OS X Lion 10.7.



(1.2) Facebook’s URL Redirection System Related to “*.php” Files

All URLs’ redirection are based on several files, such l.php, a.php, landing.php and so on.

The main redirection are based on file “l.php” (Almost all redirection links are using it right now).

For file “l.php”, one parameter “h” is used for authentication. When it mentions to file “a.php”, parameter “eid” is used for authentication. All those two files use parameter “u” for the url redirected to. In some other files such as “landing.php”, parameters such as “url”, “next” are used.

<1>For parameter “h”, two forms of authentication are used.

<a>h=HAQHyinFq

<b>h=hAQHalW1CAQHrkVIQNNqgwhxRWLNsFVeH3auuImlbR1CgKA

<2>For parameter “eid”, one form of authentication is used.

<a>eid=AQLP8sRq6lbU0jz0lARx9A9uetB6FIF1N2-Yjj_ePj0d_ezubjstZeDo6qDsalKVJwy6uDb_hQ-9tBsA2dVoQRq0lniOu0os_gPe3gY5l8lYblhQSwBtdvgjXjNqaxLZMYoasr3vv46tFsh1fL7q4kjT2LFw52dnJWd4SE8qc0YuPWfgPeQywgM2wl0CoW-lftWkr2dX0dLcytyHjXnvhKfVS_pQBllszUzsPENxE6EuZ-53Lh188o56idnfyyk2L58pE7C94PF-za4ZVB0qbuA2EnPcSJI-7oIiIJmIhifHe0CYTzG512-Z_heN44VlyJHevhS9auAR8-lFCAIlYymnT_Qiwp92RxjNOfBypBvszQUrvB6PH3fANn1prfMBVm4RD_GFel14KVDS5USswbTOTkL3sZNhHUqqPHwBwU3JFePMMuwsfesigH85B_AxCsXUIWN7klKGSq8bPPsKSHttsa9hkkMpSfRKL7D_xwW4dU2xlmfGWil7jYRJmwfbOeF0zujk1FRBuM757tbfFMav-J-K9npbdrDrCuUVqV__Tf7CGZ89nPl-M2d09pE9enJj0OBXOaSXZX16LKaYnv1Wh4GKme7C-EOunITxyQtp1zy-48Uaz9mxO2x4bw7sBDfzDStF_Al8_0SMjWNTh-J38rBHAgT96X-dPFI43HU3x3fVymE9szrclBpvTaSfYezatgMzf77s3lQrQAMSlwSSRIzRuoFvQBmWKT0T5ZFgH5ykhYKhNMiKj577UO5g2Ojm-_-KKF4N_DBuG5R-I6EOSlhok2xUkpKVDnDcxZFTLxGmx5xc56J5kZLjJ96wnF2fH09Q19Qc2aU3xYFlEFrKjrlLpwGyOyCDx7_z7y1O4Efqew3Fa0Cb9s6Kk2jpLF5XEIaYzzXOLAffxXG6icBJVovb9RPmiZ5s9dKYYotLol68_X04O05bEvVccPEh-IQwX_VTMt3f23be2MECEqR2l1A1ZkJx4qP00GI1pZhU_CXAnjSaTNmtaINRUeSsLNEZZsPwpWJMfeeGSwuof9krC05eSWjO0jH9tua0KteMYhj8i-3dwSBp4f7nMcFwH5ltfCLhMCYNB8rxgzcAczyhLIo2UY-3FSaJXBZ0lvuZBvnj7myUnyc2lCcy-fWh93MRRaJrrinjtfr9fDSMHM9Cja5xi0eG3Vs0aClnWbeJZA79TvmYt7E53HfwGuv5-EJOqRh3cwZF-53uPHA73ikUk3xTApjQunJM4uIBhpy7iBIgn_OXXo3X03YUJtJcDuC20ocJbZ310VHliox5tYZF2oiMaOfgo9Y9KeqgsrJgwPCJeif4aB0Ne4g_oM_Tuqt2pXbdgoCawHIApF087eFKJqejp0jpEkJerXPyK-IqsD_SQfIm_2WJSkzwzATwQKs

 

 

 


(2) Vulnerability Description 1:

(2.1) A security researcher reported two Open Redirect vulnerabilities to Facebook in 2013. The following are the two links reported.

Though a new mechanism was adopted. However, all old generated redirections still work by parameter “h” and “eid”.

 

 

(2.2) A website was used for the following tests. The website is “http://www.tetraph.com/“. Suppose this website is malicious.

(2.2.1)

<1>First test

<a>file: “l.php”

<b>URL parameter: “u”

<c>authentication parameter: “h”

<d>form: “h=HAQHyinFq”.

<e>The authentication has no relation with all other parameters, such as “s”.

Examples:

URL 1:

Redirect Forbidden:

Redirect Works:

 

URL 2:

Redirect Forbidden:

Redirect Works:

 

 

(2.2.2)

<2>Second test. It is the same situation as above.

<a>file: “l.php”,

<b>url parameter “u”

<c>authentication parameter: “h”

<d>form: “h=hAQHalW1CAQHrkVIQNNqgwhxRWLNsFVeH3auuImlbR1CgKA”.

<e>The authentication has no relation to all other parameters, such as “env”, “s”.

 

Examples:

URL 1:

Redirect Forbidden:

 

URL 2:

Redirect Forbidden:

Redirect Works:

 

 

 

(3) Facebook File “a.php” Open Redirect Security Vulnerability

 

(3.1)

<a>file: “a.php”

<b>parameter “u”

<c> authentication parameter: “eid”

<d> form: “eid=5967147530925355409.6013336879369.AQKBG5nt468YgKeiSdgExZQRjwGb9r6EOu-Uc5WPvi-EVHEzadq8YSrgSvUzbMmxKPPfTgM-JrPff7tN38luc-8h16lxL0Gj_4qs1-58yWgXirMH4AEf8sOEsZc5DTx7yFndgODvD5NrC-314BIj4pZvMhlljXv89lHRH6pBgyGGVm-oWBDIF8CuRER1f5ZGbKdsiUcBISdWTninVzvBdW1mZY0SWzqT21fZmhgVKtdkRf5l_pag7hAmotFK9HI5XHfGicWVqzRyTNiDIYjyVjTv4km2FOEp7WP3w65aVUKP_w”.

<e>The authentication has no relation to all other parameters, such as “mac”, “_tn_”.

Examples:

Vulnerable URL:

https://www.facebook.com/a.php?u=http%3A%2F%2Ffb-nym.adnxs.com%2Ffclick%3Fclickenc%3Dhttp%253A%252F%252Fbs.serving-sys.com%252FBurstingPipe%252FadServer.bs%253Fcn%253Dtf%2526c%253D20%2526mc%253Dclick%2526pli%253D8782431%2526PluID%253D0%2526ord%253D%257BCACHEBUSTER%257D%26cp%3D%253Fdi%253DzGxX6INl-T9QvRSibN_3P5qZmZmZmfk_UL0Uomzf9z_ObFfog2X5P_WPPCuD-to_CKEeLew3cQIQkc9SAAAAAHQcDQB2BQAAKAcAAAIAAAD4iq8AanMCAAAAAQBVU0QAVVNEAGMASABq4DoFka4BAgUCAQUAAIgAkinLswAAAAA.%252Fcnd%253D%252521qQYdPgjeqqYBEPiVvgUY6uYJIAA.%252Freferrer%253Dfacebook.com%252F&mac=AQJllyaGzLYoRoQz&__tn__=%2AB&eid=5967147530925355409.6013336879369.AQKBG5nt468YgKeiSdgExZQRjwGb9r6EOu-Uc5WPvi-EVHEzadq8YSrgSvUzbMmxKPPfTgM-JrPff7tN38luc-8h16lxL0Gj_4qs1-58yWgXirMH4AEf8sOEsZc5DTx7yFndgODvD5NrC-314BIj4pZvMhlljXv89lHRH6pBgyGGVm-oWBDIF8CuRER1f5ZGbKdsiUcBISdWTninVzvBdW1mZY0SWzqT21fZmhgVKtdkRf5l_pag7hAmotFK9HI5XHfGicWVqzRyTNiDIYjyVjTv4km2FOEp7WP3w65aVUKP_w

POC:

 

(3.2) Facebook Login Page Covert Redirect Security Vulnerability

Vulnerable URL Related to Login.php Based on a.php:

https://www.facebook.com/login.php?next=https%3A%2F%2Fwww.facebook.com%2Fa.php%3Fu%3Dhttp%253A%252F%252Fwww.rp.edu.sg%252Fopenhouse2014%252F%253Futm_source%253Dfacebook%2526utm_medium%253Dcpc%2526utm_campaign%253Dopenhouse2014%26mac%3DAQKyRHClixA20iGL%26__tn__%3D%252AB%26eid%3DAQLAHC7szSXhT3FaEBXe5YFsOC0kEM4nN9PlVovdilvuzROStFXoYqptlKpcJAzHNTLpxWAIrmJYsR6RVG_Htk6pgT7Iol6lWHDJvn7Cg5sqigvE_eVS895Eh6fSwxH3fgfWcNDrEl5_lFgRbrJtC71R68rW_VXS9QCN7Po9wTWDnbyZTaXawdrdQyibryvA56Spr5GcUDUboRFxy8YSr2ahUV_goDAQA3OKmCACEn8CmyMrOT5gZq3iwusysdchRxLIv5N82-GMTiDxXXgkDYf1P7XwvklWpfy_cEItZzV5v0P7fRZB3qiq_RDx9jhEzndlJhUJL2aWE0ldPmGKGz9xWyvPaPLOwzBo23GQbpj2ZN_tw9B9tz2l3tGIN1yegd_Wf6PSFIZOuBXfZILvmILcxg3qz4dHx1fmgPZBpf_34mPnMEkgZqbT2WeV_GZKz8RDIg88D3vrmwyMwWxeh3xyGuddjZUjOUjPCUwrgSrWZK3XHRA7TA7tWIsQ4X1bsjx9c72mm8bZmmRBRJwqOcjsW0QEVETs_Cs9pS9QBkgX8yVPJCHuk1v_xkj4EHHH9sNP7a4GRs8olklBTKhCcJ908sVrQVT2I-cQYw2SVU9hWaWWjX2AGt3WpdT2kx6SIPoPQpX5cIC4Lcfaa7EcZFBnoQPv3mR5BNHRFTh_6Qvr01BrCG3Fv5VeDeXhM8cHk6VuBtj5smz0ZeGT5JWvub5ORJ4xzVN0zAW8V4qiKiVFKTEFMZASaZFon41VFCbhxkX0Bi62Ko64PY6uP64tCMWh6yX2o0JMc0mJWFJRp1695OCKgLXf0udRyWDESTyYgJXIlxecCmlwCEbleAsE-wtDXNOfDTXOzApr1sZO_58FBRaw-K4Z2VRXLir5mrdXTKnM1Y4rDDqGZur9G7LfuXrCr5oR1J5LJ8sVupHqsiN7-UqdakiEEIBq750KxVjaAdCyqJp_5EJ-yVMK3f2pMX7cQ2Lw6u434hHimuLN9VDPLkpSiMlPOa8RkarDSred73IfQiv-PluegYDfunZFxj1KvcAlzhVZsL-a52hJmXrOrzKuV0hyZaBLtAIo6AEoXXV30D-6iraSUphkOFzYt3ah6oRrmXLQZKm2E8Cuag5d_rAnwvIr98dn4OSa8Z4MCZemI3uH8cjxr86aE046uTA_Hm1GjYM5l7wkpHknHI8QR2q5Cioo2h6WiUO-jsIFkQ4XFgAd5IUCcAbQukXdC4GJzl18iaN8wkylsTk8aVBn6G1xZadSL0b5R3NgsYfQUVtV0g9slnOLNkgq0NLMAk0kWFs

POC:

https://www.facebook.com/login.php?next=https%3A%2F%2Fwww.facebook.com%2Fa.php%3Fu%3Dhttp%253A%252F%252Fwww.stackoverflow.com%26mac%3DAQKyRHClixA20iGL%26__tn__%3D%252AB%26eid%3DAQLAHC7szSXhT3FaEBXe5YFsOC0kEM4nN9PlVovdilvuzROStFXoYqptlKpcJAzHNTLpxWAIrmJYsR6RVG_Htk6pgT7Iol6lWHDJvn7Cg5sqigvE_eVS895Eh6fSwxH3fgfWcNDrEl5_lFgRbrJtC71R68rW_VXS9QCN7Po9wTWDnbyZTaXawdrdQyibryvA56Spr5GcUDUboRFxy8YSr2ahUV_goDAQA3OKmCACEn8CmyMrOT5gZq3iwusysdchRxLIv5N82-GMTiDxXXgkDYf1P7XwvklWpfy_cEItZzV5v0P7fRZB3qiq_RDx9jhEzndlJhUJL2aWE0ldPmGKGz9xWyvPaPLOwzBo23GQbpj2ZN_tw9B9tz2l3tGIN1yegd_Wf6PSFIZOuBXfZILvmILcxg3qz4dHx1fmgPZBpf_34mPnMEkgZqbT2WeV_GZKz8RDIg88D3vrmwyMwWxeh3xyGuddjZUjOUjPCUwrgSrWZK3XHRA7TA7tWIsQ4X1bsjx9c72mm8bZmmRBRJwqOcjsW0QEVETs_Cs9pS9QBkgX8yVPJCHuk1v_xkj4EHHH9sNP7a4GRs8olklBTKhCcJ908sVrQVT2I-cQYw2SVU9hWaWWjX2AGt3WpdT2kx6SIPoPQpX5cIC4Lcfaa7EcZFBnoQPv3mR5BNHRFTh_6Qvr01BrCG3Fv5VeDeXhM8cHk6VuBtj5smz0ZeGT5JWvub5ORJ4xzVN0zAW8V4qiKiVFKTEFMZASaZFon41VFCbhxkX0Bi62Ko64PY6uP64tCMWh6yX2o0JMc0mJWFJRp1695OCKgLXf0udRyWDESTyYgJXIlxecCmlwCEbleAsE-wtDXNOfDTXOzApr1sZO_58FBRaw-K4Z2VRXLir5mrdXTKnM1Y4rDDqGZur9G7LfuXrCr5oR1J5LJ8sVupHqsiN7-UqdakiEEIBq750KxVjaAdCyqJp_5EJ-yVMK3f2pMX7cQ2Lw6u434hHimuLN9VDPLkpSiMlPOa8RkarDSred73IfQiv-PluegYDfunZFxj1KvcAlzhVZsL-a52hJmXrOrzKuV0hyZaBLtAIo6AEoXXV30D-6iraSUphkOFzYt3ah6oRrmXLQZKm2E8Cuag5d_rAnwvIr98dn4OSa8Z4MCZemI3uH8cjxr86aE046uTA_Hm1GjYM5l7wkpHknHI8QR2q5Cioo2h6WiUO-jsIFkQ4XFgAd5IUCcAbQukXdC4GJzl18iaN8wkylsTk8aVBn6G1xZadSL0b5R3NgsYfQUVtV0g9slnOLNkgq0NLMAk0kWFs





Those vulnerabilities were reported to Facebook in 2014 and they have been patched.





Several other similar products 0-day vulnerabilities have been found by some other bug hunter researchers before. Facebook has patched some of them. “The Full Disclosure mailing list is a public forum for detailed discussion of vulnerabilities and exploitation techniques, as well as tools, papers, news, and events of interest to the community. FD differs from other security lists in its open nature and support for researchers’ right to decide how to disclose their own discovered bugs. The full disclosure movement has been credited with forcing vendors to better secure their products and to publicly acknowledge and fix flaws rather than hide them. Vendor legal intimidation and censorship attempts are not tolerated here!” All the fllowing web securities have been published here, Buffer overflow, HTTP Response Splitting (CRLF), CMD Injection, SQL injection, Phishing, Cross-site scripting, CSRF, Cyber-attack, Unvalidated Redirects and Forwards, Information Leakage, Denial of Service, File Inclusion, Weak Encryption, Privilege Escalation, Directory Traversal, HTML Injection, Spam. Large number of Facebook bugs were published here. FD also publishes suggestions, advisories, solutions details related to Open Redirect vulnerabilities and cyber intelligence recommendations.








(4) Amazon Covert Redirect Security Vulnerability Based on Facebook

Since Facebook is trusted by large numbers of other websites. Those vulnerabilities can be used to do “Covert Redirect” to other websites such as Amazon.


Domain:
http://www.amazon.com


“American electronic commerce company with headquarters in Seattle, Washington. It is the largest Internet-based retailer in the United States. Amazon.com started as an online bookstore, but soon diversified, selling DVDs, Blu-rays, CDs, video downloads/streaming, MP3 downloads/streaming, software, video games, electronics, apparel, furniture, food, toys and jewelry. The company also produces consumer electronics—notably, Amazon Kindle e-book readers, Fire tablets, Fire TV and Fire Phone — and is a major provider of cloud computing services. Amazon also sells certain low-end products like USB cables under its inhouse brand AmazonBasics. Amazon has separate retail websites for United States, United Kingdom & Ireland, France, Canada, Germany, The Netherlands, Italy, Spain, Australia, Brazil, Japan, China, India and Mexico. Amazon also offers international shipping to certain other countries for some of its products. In 2011, it had professed an intention to launch its websites in Poland and Sweden.” (Wikipedia)

 

 

The vulnerability exists at “redirect.html?” page with “&location” parameter, e.g.

 

(4.1) When a user is redirected from Amazon to another site, Amazon will check parameters “&token”. If the redirected URL’s domain is OK, Amazon will allow the reidrection.

However, if the URLs in a redirected domain have open URL redirection vulnerabilities themselves, a user could be redirected from Amazon to a vulnerable URL in that domain first and later be redirected from this vulnerable site to a malicious site. This is as if being redirected from Amazon directly.

One of the vulnerable domain is,
http://www.facebook.com

 

(4.2) Use one of webpages for the following tests. The webpage address is “http://www.inzeed.com/kaleidoscope“. Suppose it is malicious.

Vulnerable URL:

POC:

 

 

 

 

 

Related Articles:
http://seclists.org/fulldisclosure/2015/Jan/22
http://permalink.gmane.org/gmane.comp.security.fulldisclosure/1428
http://lists.openwall.net/full-disclosure/2015/01/12/1
http://marc.info/?l=full-disclosure&m=142104333521454&w=4
http://diebiyi.com/articles/security/facebook-open-redirect/
https://www.facebook.com/essaybeans/posts/570476126427191
http://germancast.blogspot.de/2015/06/facebook-web-security-0day-bug.html
https://mathfas.wordpress.com/2015/01/11/facebook-open-redirect/
http://essaybeans.lofter.com/post/1cc77d20_7300027
http://qianqiuxue.tumblr.com/post/120750458855/itinfotech-facebook-web-security-0day-bug
https://www.facebook.com/permalink.php?story_fbid=472994806188548&id=405943696226993
https://mathfas.wordpress.com/2015/01/11/facebook-open-redirect/
http://www.tetraph.com/blog/phishing/facebook-open-redirect/
http://itinfotech.tumblr.com/post/120750347586/facebook-web-security-0day-bug
http://ittechnology.lofter.com/post/1cfbf60d_72fd108
http://russiapost.blogspot.ru/2015/06/facebook-web-security-0day-bug.html
https://twitter.com/tetraphibious/status/606676645265567744
https://plus.google.com/u/0/110001022997295385049/posts/hb6seddG561
http://whitehatpost.blog.163.com/blog/static/24223205420155501020837/
http://www.inzeed.com/kaleidoscope/computer-security/facebook-open-redirect/







OAuth and OpenID Users Threatened by New Security Flaw, Covert Redirect

heartbleed_bug_hackers

 

A serious flaw in two widely used security standards could give anyone access to your account information at Google, Microsoft, Facebook, Twitter and many other online services. The flaw, dubbed “Covert Redirect” by its discoverer, exists in two open-source session-authorization protocols, OAuth 2.0 and OpenID.

 

Both standards are employed across the Internet to let users log into websites using their credentials from other sites, such as by logging into a Web forum using a Facebook or Twitter username and password instead of creating a new account just for that forum.

 

Attackers could exploit the flaw to disguise and launch phishing attempts from legitimate websites, said the flaw’s finder, Mathematics Ph.D. student Wang Jing of the Nanyang Technological University in Singapore.

 

Wang believes it’s unlikely that this flaw will be patched any time soon. He says neither the authentication companies (those with which users have an account, such as Google, Microsoft, Facebook, Twitter or LinkedIn, among others) nor the client companies (sites or apps whose users log in via an account from an authentication company) are taking responsibility for fixing the issue.

 

“The vulnerability is usually due to the existing weakness in the third-party websites,” Wang writes on his own blog. “However, they have little incentive to fix the problem.”

 

The biggest danger of Covert Redirect is that it could be used to conduct phishing attacks, in which cybercriminals seize login credentials, by using email messages containing links to malicious websites disguised as something their targets might want to visit.

 

Normal phishing attempts can be easy to spot, because the malicious page’s URL will usually be off by a couple of letters from that of the real site. The difference with Covert Redirect is that an attacker could use the real website instead by corrupting the site with a malicious login popup dialogue box.

 

For example, say you regularly visit a given forum (the client company), to which you log in using your credentials from Facebook (the authentication company). Facebook uses OAuth 2.0 to authenticate logins, so an attacker could put a corrupted Facebook login popup box on this forum.

 

If you sign in using that popup box, your Facebook data will be released to the attacker, not to the forum. This means the attacker could possibly gain access to your Facebook account, which he or she could use to spread more socially engineered attacks to your Facebook friends.

 

Covert Redirect could also be used in redirection attacks, which is when a link takes you to a different page than the one expected.

 

Wang told CNET authentication companies should create whitelists — pre-approved lists that block any not on it — of the client companies that are allowed to use OAuth and OpenID to redirect to them. But he said he had contacted a number of these authentication companies, who all shifted blame elsewhere.

 

Wang told CNET Facebook had told him it “understood the risks associated with OAuth 2.0” but that fixing the flaw would be “something that can’t be accomplished in the short term.” Google and LinkedIn allegedly told Wang they were looking into the issue, while Microsoft said the issue did not exist on its own sites.

 

Covert Redirect appears to exist in the implementations of the OpenID and OAuth standards used on client websites and apps. But because these two standards are open-source and were developed by a group of volunteers, there’s no company or dedicated team that could devote itself to fixing the issue.

 

 

Where does that leave things?

“Given the trust users put in Facebook and other major OAuth providers, I think it will be easy for attackers to trick people into giving some access to their personal information stored on those service,” Chris Wysopal, chief technology officer of Boston-area security firm Veracode and a member of the legendary 1990s hackerspace the L0pht, told CNET.

 

“It’s not easy to fix, and any effective remedies would negatively impact the user experience,” Jeremiah Grossman, founder of Santa Clara, Calif.-based WhiteHat Security, told CNET. “Just another example that Web security is fundamentally broken and the powers that be have little incentive to address the inherent flaws.”

 

Users should be extra-wary of login popups on Web pages. If you wish to log into a given website, it might be better to use an account specific to that website instead of logging in with Facebook, Twitter, or another authentication company, which would require the use of OAuth and/or OpenID to do.

 

If you think someone has gained access to one of your online accounts, notify the service and change that account’s password immediately.

 

 

 

 

 

Related Articles:

http://www.tomsguide.com/us/facebook-google-covert-redirect-flaw,news-18726.html

http://www.scmagazine.com/covert-redirect-vulnerability-impacts-oauth-20-openid/article/345407/

http://news.yahoo.com/facebook-google-users-threatened-security-192547549.html

http://thehackernews.com/2014/05/nasty-covert-redirect-vulnerability.html

http://www.foxnews.com/tech/2014/05/05/facebook-google-users-threatened-by-new-security-flaw/

http://whitehatview.tumblr.com/post/120695795041

http://russiapost.blogspot.ru/2015/05/openid-oauth-20.html

http://www.diebiyi.com/articles/security/covert-redirect/covert_redirect/

https://itswift.wordpress.com/2014/05/06/microsoft-google-facebook-attacked/

http://tetraph.blog.163.com/blog/static/2346030512015420103814617/

http://itsecurity.lofter.com/post/1cfbf9e7_72e2dbe

http://ithut.tumblr.com/post/119493304233/securitypost-une-faille-dans-lintegration

http://japanbroad.blogspot.jp/2015/05/oauthopenid-facebook.html

http://webtech.lofter.com/post/1cd3e0d3_6f0f291

https://webtechwire.wordpress.com/2014/05/11/covert-redirect-attack-worldwide/

http://whitehatview.tumblr.com/post/119489968576/securitypost-sicherheitslucke-in-oauth-2-0-und

http://www.inzeed.com/kaleidoscope/computer-security/facebook-google-attack/

 

 

 

 

 

Facebook OAuth 2.0 Covert Redirect Vulnerability based on Ask.com (Information Leakage and URL Redirect)

facebook-jpg

 

 

Facebook OAuth 2.0 Service Covert Redirect Web Security Bugs Based on Ask.com (Information Leakage & Open Redirect)



(1) Domain:
facebook.com

 

“Facebook had over 1.44 billion monthly active users as of March 2015. Because of the large volume of data users submit to the service, Facebook has come under scrutiny for their privacy policies. Facebook, Inc. held its initial public offering in February 2012 and began selling stock to the public three months later, reaching an original peak market capitalization of $104 billion. As of February 2015 Facebook reached a market capitalization of $212 Billion.” (Wikipedia)

 

 

 

(2) Vulnerability Description:

Facebook web application has a computer security problem. Hacker can exploit it by Covert Redirect cyber attacks. 



The vulnerabilities can be attacked without user login. Tests were performed on Microsoft IE (10.0.9200.16750) of Windows 8, Mozilla Firefox (34.0) & Google Chromium 39.0.2171.65-0 ubuntu0.14.04.1.1064 (64-bit) of Ubuntu (14.04),Apple Safari 6.1.6 of Mac OS X Lion 10.7. 

 
 
 

 


(2.1) Vulnerability Description:

Facebook’s SSO system is susceptible to Attacks. More specifically, the authentication of parameter “&redirct_uri” in SSO system is insufficient. It can be misused to design Open Redirect Attacks to Facebook.At the same time, it can be used to collect sensitive information of both third-party app and users by using the following parameters,

“&response_type”=sensitive_info,token…

“&scope”=email,user_birthday,user_likes.­..

 

 

It increases the likelihood of successful Open Redirect Attacks to third-party websites, too.

 

The vulnerabilities occurs at page “/dialog/oauth?” with parameter “&redirect_uri”, e.g.
https://www.facebook.com/dialog/oauth?client_id=152973104736490&redirect_uri=http%3A%2F%2Fwzus.ask.com%2Fr%3Ft%3Dp%26u%3Dhttp%3A%2F%2Fwww.tetraph.com%2Fessayjeans%2Fpoems%2Fdistance.html%3F&response_type=code&scope=email%2cuser_location%2cuser_birthday&display=popup [1]

 

 

Before acceptance of third-party application:

 

When a logged-in Facebook user clicks the URL ([1]) above, he/she will be asked for consent as in whether to allow a third-party website to receive his/her information. If the user clicks OK, he/she will be then redirected to the URL assigned to the parameter “&redirect_uri”.

 

If a user has not logged onto Facebook and clicks the URL ([1]) above, the same situation will happen upon login.

 

After acceptance of third-party application:

 

A logged-in Facebook user would no longer be asked for consent and could be redirected to a webpage controlled by the attacker when he/she clicks the URL ([1]).

 

For a user who has not logged in, the attack could still be completed after a pop-up page that prompts him/her to log in.

 

 

 

 

(2.1.1) Facebook would normally allow all the URLs that belong to the domain of an authorized third-party website. However, these URLs could be prone to manipulation. For example, the “&redirect_uri” parameter in the URLs is supposed to be set by the third-party websites, but an attacker could change its value to make Attacks.

 

Hence, a user could be redirected from Facebook to a vulnerable URL in that domain first and later be redirected from this vulnerable site to a malicious site unwillingly. This is as if the user is redirected from Facebook directly. The number of Facebook’s SSO client websites is so huge that such Attacks could be commonplace.

 

Before acceptance of the third-party application, Facebook’s SSO system makes the redirects appear more trustworthy and could potentially increase the likelihood of successful Open Redirect Attacks of third-party website.

 

Once the user accepts the application, the attackers could completely bypass Facebook’s authentication system and attack more easily.

 

It might be of Facebook’s interest to patch up against such attacks.

 

 

 

 

(2.2) Used one of webpages for the following tests. The webpage is “http://www.diebiyi.com/articles“. We can suppose it is malicious and contains code that collect sensitive information of both third-party app and users.

 

Below is an example of a vulnerable third-party domain:
ask.com

 

 

Vulnerable URL in this domain:
http://wzap.ask.com/r?t=v&d=im&u=http%3A%2F%2Ftetraph.com

 

Vulnerable URL from Facebook that is related to ask.com:
https://www.facebook.com/dialog/oauth?client_id=152973104736490&redirect_uri=https%3a%2f%2fsocial.ask.com%2fGS%2fGSLogin.aspx%3fst%3dzNQz0TjIZd42P_zI5MUVw5WtCHw7EDMc1YEjBVuz3bU.&response_type=code&scope=email%2cuser_location%2cuser_birthday&display=popup

 

POC:
https://www.facebook.com/dialog/oauth?client_id=152973104736490&redirect_uri=http%3A%2F%2Fwzus.ask.com%2Fr%3Ft%3Dp%26u%3Dhttp%3A%2F%2Fwww.tetraph.com%2Fessayjeans%2Fpoems%2Fdistance.html%3F&response_type=code&scope=email%2cuser_location%2cuser_birthday&display=popup

 

 

 

 

(2.3) The following URLs have the same vulnerabilities.
https://m.facebook.com/dialog/oauth?redirect_uri=http%3A%2F%2Fm.espn.go.com%2Fwireless%2Fconnect&scope=email%2Cuser_birthday%2Cuser_likes&client_id=116656161708917

https://graph.facebook.com/oauth/authorize?client_id=116656161708917&redirect_uri=http://m.espn.go.com/wireless/connect&display=touch&scope=email,user_birthday,user_likes

http://www.facebook.com/dialog/feed?app_id=180444840287&link=http://www.theguardian.com/money/2007/apr/21/creditcards.debt&display=popup&redirect_uri=http://gu-social-share-experiments.theguardian.com&show_error=false&ref=desktop

https://api.instagram.com/oauth/authorize/?client_id=28ad60e4d0b14b5c8bd87099e53feaef&redirect_uri=http%3A%2F%2Ffollowgram.me%2Flogin&response_type=code&scope=likes+comments+relationships&display=touch

 

 


POC Video:
https://www.youtube.com/watch?v=Y2-2Scp0pbs



 

Blog Detail:
http://www.tetraph.com/blog/covert-redirect/facebook-oauth-2-0-covert-redirect-vulnerability-based-on-ask-com-information-leakage-and-url-redirect/




 

(3) What is Covert Redirect? 

Covert Redirect is a class of security bugs disclosed in May 2014. It is an application that takes a parameter and redirects a user to the parameter value without sufficient validation. This often makes use of Open Redirect and XSS (Cross-site Scripting) vulnerabilities in third-party applications.

 
 

Covert Redirect is also related to single sign-on. It is known by its influence on OAuth and OpenID. Hacker may use it to steal users’ sensitive information. Almost all OAuth 2.0 and OpenID providers worldwide are affected. Covert Redirect can work together with CSRF (Cross-site Request Forgery) as well. 

 
 
 
 



 

Discover and Reporter:
Wang Jing, Division of Mathematical Sciences (MAS), School of Physical and Mathematical Sciences (SPMS), Nanyang Technological University (NTU), Singapore. 
(@justqdjing)
http://tetraph.com/wangjing/










Related Articles:
http://tetraph.com/security/covert-redirect/facebook-oauth-2-0-covert-redirect-vulnerability-based-on-ask-com-information-leakage-and-url-redirect/
https://twitter.com/tetraphibious/status/559169008889389056
http://tetraph.blogspot.com/2014/05/hack-facebook-account-based-on-oauth-20.html
http://tetraph.blog.163.com/blog/static/23460305120144210374933/
http://computerobsess.blogspot.com/2014/09/facebook-bug.html
http://webcabinet.tumblr.com/post/120699361942/whitehatview-internet-users-threatened-by-new
http://webtech.lofter.com/post/1cd3e0d3_72e61df
http://www.inzeed.com/kaleidoscope/covert-redirect/facebook-oauth-2-0-covert-redirect-vulnerability-based-on-ask-com-information-leakage-and-url-redirect/