Vulnerability Database

308,379

Total vulnerabilities in the database

CVE-2019-18800

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. 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.

  • Published: Nov 6, 2019
  • Updated: Nov 9, 2025
  • CVE: CVE-2019-18800
  • Severity: High
  • Exploit:

CVSS v3:

  • Severity: High
  • Score: 8.8
  • AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CVSS v2:

  • Severity: Low
  • Score: 4.3
  • AV:N/AC:M/Au:N/C:P/I:N/A:N