Off-by-one in UltraVNC - CVE-2019-8268
Published: November 26, 2019 / Updated: November 27, 2019
Vulnerability identifier: #VU22988
CSH Severity: Medium
CVSS v4: 8.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2019-8268
CWE-ID: CWE-193
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to an off-by-one error in VNC client code connected with improper usage of "ClientConnection::ReadString" function. A remote attacker that controls a malicious VNC server can trick a user to connect to it, trigger an off-by-one error and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
Affected software
UltraVNC
How to mitigate CVE-2019-8268
Install updates from vendor's website.
UltraVNC - update to 1.2.2.3