CVE-2018-20679 Information disclosure in n/a

High 7.5 Published 9 Jan 2019 Updated 9 Jun 2025

A remote attacker can leak sensitive stack information from BusyBox DHCP components by sending a crafted DHCP message.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2018-20679?

CVE-2018-20679 is a high-severity vulnerability in Canonical Ubuntu Linux, published on 9 Jan 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

An issue was discovered in BusyBox before 1.30.0. An out of bounds read in udhcp components (consumed by the DHCP server, client, and relay) allows a remote attacker to leak sensitive information from the stack by sending a crafted DHCP message. This is related to verification in udhcp_get_option() in networking/udhcp/common.c that 4-byte options are indeed 4 bytes.

Weakness: CWE-125

Which versions are affected by CVE-2018-20679?

It affects 2 products.

Products include Busybox Busybox, Canonical Ubuntu Linux.

How do I fix CVE-2018-20679?

Upgrade to a fixed version.

Is CVE-2018-20679 being exploited?

There is no known exploitation of CVE-2018-20679 in the wild and no public exploit code.

All Canonical Ubuntu Linux vulnerabilities

Sources

Also known as ALPINE-CVE-2018-20679, DEBIAN-CVE-2018-20679, GHSA-73q8-6p6h-wvfh, UBUNTU-CVE-2018-20679.