Showing posts with label Covert.Redirect. Show all posts
Showing posts with label Covert.Redirect. Show all posts

Friday, 5 June 2015

Yahoo Yahoo.com Yahoo.co.jp Open Redirect (Unvalidated Redirects and Forwards) Web Security Bugs














Yahoo Yahoo.com Yahoo.co.jp Open Redirect (Unvalidated Redirects and Forwards) Web Security Bugs



Though Yahoo lists open redirect vulnerability on its bug bounty program. However, it seems Yahoo do not take this vulnerability seriously at all.

Multiple Open Redirect vulnerabilities were reported Yahoo. All Yahoo's responses were "It is working as designed". However, these vulnerabilities were patched later.

Several other security researcher complained about getting similar treatment, too.


All Open Redirect Vulnerabilities are intended behavior? If so, why patch them later?




From report of CNET, Yahoo's users were attacked by redirection vulnerabilities. "Yahoo.com visitors over the last few days may have been served with malware via the Yahoo ad network, according to Fox IT, a security firm in the Netherlands. Users visiting pages with the malicious ads were redirected to sites armed with code that exploits vulnerabilities in Java and installs a variety of different malware. "
http://www.cnet.com/news/yahoo-users-exposed-to-malware-attack/


Moreover, since Yahoo is well-known worldwide. these vulnerabilities can be used to attack other companies such as Google, eBay, The New York Times, Amazon, Godaddy, Alibaba, Netease, e.g. by bypassing their Open Redirect filters (Covert Redirect). These cyber security bug problems have not been patched. Other similar web and computer flaws will be published in the near future.



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. 


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


Both Yahoo and Yahoo Japan online web application has a computer cyber security bug problem. It can be exploited by Unvalidated Redirects and Forwards (URL Redirection) 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.


BugTraq is a full disclosure moderated mailing list for the *detailed* discussion and announcement of computer security vulnerabilities: what they are, how to exploit them, and how to fix them. The below things be posted to the Bugtraq list: (a) Information on computer or network related security vulnerabilities (UNIX, Windows NT, or any other). (b) Exploit programs, scripts or detailed processes about the above. (c) Patches, workarounds, fixes. (d) Announcements, advisories or warnings. (e) Ideas, future plans or current works dealing with computer/network security. (f) Information material regarding vendor contacts and procedures. (g) Individual experiences in dealing with above vendors or security organizations. (h) Incident advisories or informational reporting. (i) New or updated security tools. A large number of the fllowing web securities have been published here, Injection, Broken Authentication and Session Management, Cross-Site Scripting (XSS), Insecure Direct Object References, Security Misconfiguration, Sensitive Data Exposure, Missing Function Level Access Control, Cross-Site Request Forgery (CSRF), Using Components with Known Vulnerabilities, Unvalidated Redirects and Forwards. It also publishes suggestions, advisories, solutions details related to Open Redirect vulnerabilities and cyber intelligence recommendations.


(1) Yahoo.com Open Redirect


Domain:
yahoo.com

"Yahoo Inc. (styled as Yahoo!) is an American multinational technology company headquartered in Sunnyvale, California. It is globally known for its Web portal, search engine Yahoo Search, and related services, including Yahoo Directory, Yahoo Mail, Yahoo News, Yahoo Finance, Yahoo Groups, Yahoo Answers, advertising, online mapping, video sharing, fantasy sports and its social media website. It is one of the most popular sites in the United States. According to news sources, roughly 700 million people visit Yahoo websites every month. Yahoo itself claims it attracts more than half a billion consumers every month in more than 30 languages. Yahoo was founded by Jerry Yang and David Filo in January 1994 and was incorporated on March 1, 1995. Marissa Mayer, a former Google executive, serves as CEO and President of the company." (Wikipedia)

Vulnerable URLs:




Poc Video:
https://www.youtube.com/watch?v=k4eFLsTyZkg

Another Yahoo Open Rediect Vulnerability Video Published Before:




(2) Yahoo.co.jp Open Redirect


Domain:
yahoo.co.jp


"Yahoo! JAPAN Corporation (ヤフージャパン株式会社 Yafū Japan Kabushiki-gaisha?) is a Japanese internet company formed as a joint venture between the American internet company Yahoo! and the Japanese internet company SoftBank. It is headquartered at Midtown Tower in the Tokyo Midtown complex in Akasaka, Minato, Tokyo. Yahoo! Japan was listed on JASDAQ in November 1997. In January 2000, it became the first stock in Japanese history to trade for more than ¥100 million per share. The company was listed on the Tokyo Stock Exchange in October 2003 and became part of the Nikkei 225 stock market index in 2005. Yahoo! Japan acquired the naming rights for the Fukuoka Dome in 2005, renaming the dome as the "Fukuoka Yahoo! Japan Dome". The "Yahoo Dome" is the home field for the Fukuoka SoftBank Hawks, a professional baseball team majority owned by SoftBank." (Wikipedia)




Use one of webpages for the following tests. The webpage address is "http://itinfotech.tumblr.com/". Suppose that this webpage is malicious.

Vulnerable URL:

POC:











https://hackertopic.wordpress.com/2015/01/15/yahoo-yahoo-japan-vulnerable-to-spams/
https://plus.google.com/110001022997295385049/posts/4GTENtJY9XE
https://twitter.com/justqdjing/status/546910373169741825
https://www.facebook.com/pcwebsecurities/posts/701648936647693
http://homehut.lofter.com/post/1d226c81_6e6884f

https://tetraph.wordpress.com/2014/12/28/yahoo-open-redirect/
http://itinfotech.tumblr.com/post/118511508076/securitypost-yahooyahoo-japan-may-be
https://computerpitch.wordpress.com/2015/01/27/yahoo-vulnerable-to-spams/

http://testingcode.lofter.com/post/1cd26eb9_73096b9
http://lifegrey.tumblr.com/post/120767572004/yahoo-url-redirection-bug
http://blog.163.com/greensun_2006/blog/static/1112211220155565419870/
http://aibiyi.blogspot.com/2015/06/yahoo-open-redirect.html
https://www.facebook.com/tetraph/posts/1659455054274454
http://www.inzeed.com/kaleidoscope/computer-web-security/yahoo-to-spams/






Thursday, 4 June 2015

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



















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



Domain:


"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:
Jing Wang, Division of Mathematical Sciences (MAS), School of Physical and Mathematical Sciences (SPMS), Nanyang Technological University (NTU), Singapore. (@justqdjing)






(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.


More Details:


(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,


(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:









POC Video:



















Monday, 1 September 2014

GitHub Website Service OAuth 2.0 Covert Redirect Web Security Bugs (Information Leakage & Open Redirect)


















GitHub Website Service OAuth 2.0 Covert Redirect Web Security Bugs (Information Leakage & Open Redirect)



(1) Domain:
github.com


"GitHub is a web-based Git repository hosting service, which offers all of the distributed revision control and source code management (SCM) functionality of Git as well as adding its own features. Unlike Git, which is strictly a command-line tool, GitHub provides a web-based graphical interface and desktop as well as mobile integration. It also provides access control and several collaboration features such as wikis, task management, and bug tracking and feature requests for every project. GitHub offers both plans for private repositories and free accounts, which are usually used to host open-source software projects. As of 2015, GitHub reports having over 9 million users and over 21.1 million repositories, making it the largest code hoster in the world." (Wikipedia)







(2) Vulnerability Description:
GitHub 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 Detail:
GitHub's OAuth 2.0 system is susceptible to Attacks. More specifically, the authentication of parameter "&redirct_uri" in OAuth 2.0 system is insufficient. It can be misused to design Open Redirect Attacks to GitHub.


At the same time, it can be used to collect sensitive information of both third-party app and users by using the following parameters (not all apps),
"&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 "oauth/authorize?" with parameter "&redirect_uri", e.g.


Before acceptance of third-party application:
When a logged-in GitHub 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 GitHub and clicks the URL ([1]) above, the same situation will happen upon login.





After acceptance of third-party application:
A logged-in GitHub 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) GitHub 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 GitHub 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 GitHub directly. The number of GitHub's OAuth 2.0 client websites is so huge that such Attacks could be commonplace.



More seriously, some third-party websites may allow all URLs (even not belong to themselves) for "&redirect_uri" parameter.



Before acceptance of the third-party application, GitHub's OAuth 2.0 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 GitHub's authentication system and attack more easily.



It might be of GitHub's interest to patch up against such attacks. 





(2.2) Use one of my webpages for the following tests. The webpage is "http://shellmantis.tumblr.com/". 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:
travis-ci.com



Vulnerable URL from GitHub that is related to travis-ci.com:



POC:





(2.3) The following URLs have the same vulnerabilities.









POC Video:


Blog Detail:





(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:
Jing Wang, Division of Mathematical Sciences (MAS), School of Physical and Mathematical Sciences (SPMS), Nanyang Technological University (NTU), Singapore. (@justqdjing)










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