Memory leak in LibVNCServer - CVE-2018-20023

Vulnerability identifier: #VU17128

CSH Severity: Low

CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2018-20023

CWE-ID: CWE-401

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to obtain potentially sensitive information.

The vulnerability exists due memory leak in VNC Repeater client code. A remote attacker can read stack memory and bypass ASLR.

LibVNCServer
libvncserver (Debian package)
italc-client (Ubuntu package)
italc-master (Ubuntu package)
libitalccore (Ubuntu package)
Opensuse
Ubuntu

Update to version 0.9.12.

LibVNCServer - update to 0.9.12
libvncserver (Debian package) - addressed in versions 0.9.9+dfsg2-6.1+deb8u5, 0.9.11+dfsg-1.3~deb9u1
italc-client (Ubuntu package) - update to 1:3.0.3+dfsg1-3ubuntu0.1
italc-master (Ubuntu package) - update to 1:3.0.3+dfsg1-3ubuntu0.1
libitalccore (Ubuntu package) - update to 1:3.0.3+dfsg1-3ubuntu0.1

• https://ics-cert.kaspersky.com/advisories/klcert-advisories/2018/12/19/klcert-18-033-libvnc-memory-leak/

• Multiple vulnerabilities in LibVNCServer
• OpenSUSE Linux update for LibVNCServer
• Debian update for libvncserver
• Ubuntu update for italc