CVE-2018-20023 Information disclosure in LibVNC

What is CVE-2018-20023?

CVE-2018-20023 is a high-severity vulnerability in Canonical Ubuntu Linux, published on 19 Dec 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

LibVNC before 8b06f835e259652b0ff026898014fc7297ade858 contains CWE-665: Improper Initialization vulnerability in VNC Repeater client code that allows attacker to read stack memory and can be abuse for information disclosure. Combined with another vulnerability, it can be used to leak stack memory layout and in bypassing ASLR

Weakness: CWE-665

Which versions are affected by CVE-2018-20023?

It affects 3 products.

Products include Canonical Ubuntu Linux, Debian Debian Linux, Libvnc Project Libvncserver.

How do I fix CVE-2018-20023?

Apply the vendor's patch.

Is CVE-2018-20023 being exploited?

There is no known exploitation of CVE-2018-20023 in the wild and no public exploit code.

Other vulnerabilities in Canonical Ubuntu Linux

• CVE-2020-11651 SaltStack Salt Authentication Bypass Exploited Critical 9.8
• CVE-2020-7247 OpenSMTPD Remote Code Execution Exploited Critical 9.8
• CVE-2019-16928 Exim Out-of-bounds Write Exploited Critical 9.8
• CVE-2018-6789 Exim Buffer Overflow Exploited Critical 9.8
• CVE-2015-2590 Oracle Java SE and Java SE Embedded Remote Code Execution Exploited Critical 9.8

All Canonical Ubuntu Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2018-20023, GHSA-h752-h62f-w8j9, UBUNTU-CVE-2018-20023.