Viber through 11.7.0.5 Improper Input Validation Vulnerability

Summary

Viber through 11.7.0.5 allows a remote attacker who can capture a victim’s internet traffic to steal their Viber account, because not all Viber protocol traffic is encrypted. TCP data packet 9 on port 4244 from the victim’s device contains cleartext information such as the device model and OS version, IMSI, and 20 bytes of udid in a binary format, which is located at offset 0x14 of this packet.

 

 

 

 

 

 

 

 

 

 

 

Credit:

The information has been provided by Vendor

The original article can be found at:https://thesamarkand.tumblr.com/post/188785277609/viber-messenger-remote-account-reset-0day

 


Details

Then, the attacker installs Viber on his device, initiates the registration process for any phone number, but doesn’t enter a pin from SMS. Instead, he closes Viber. Next, the attacker rewrites his udid with the victim’s udid, modifying the viber_udid file, which is located in the Viber preferences folder. (The udid is stored in a hexadecimal format.) Finally, the attacker starts Viber again and enters the pin from SMS.

 

Vulnerable Systems:

Viber through 11.7.0.5 

 

CVE Information:

CVE-2019-18800

 

Disclosure Timeline:
Published Date:11/6/2019