SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

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.

HIGH 8.8EPSS 1.66%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.66%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

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.

CVSS 3.1
8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS
1.66% probability · 75th percentile
CISA KEV
Not listed
Weakness
CWE-311, CWE-319
Affected
rakuten/viber
Source
cve@mitre.org

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.