CVE-2018-20679

Name: CVE-2018-20679
Creator: NVD / NIST
Published: 2019-01-09T16:29:00.273+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 7.90%

Last modified Jun 17, 2026

CVE-2018-20679 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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. EPSS estimates a 7.90% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS Probability

7.90%

94.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Busybox	Busybox	< 1.30.0
Canonical	Ubuntu Linux	14.04
Canonical	Ubuntu Linux	16.04
Canonical	Ubuntu Linux	18.04
Canonical	Ubuntu Linux	18.10

References

http://packetstormsecurity.com/files/154361/Cisco-Device-Hardcoded-Credentials-GNU-glibc-BusyBox.html
http://seclists.org/fulldisclosure/2019/Sep/7
https://bugs.busybox.net/show_bug.cgi?id=11506Exploit, Issue Tracking, Third Party Advisory
https://busybox.net/news.htmlRelease Notes, Third Party Advisory
https://git.busybox.net/busybox/commit/?id=6d3b4bb24da9a07c263f3c1acf8df85382ff562cPatch, Third Party Advisory
https://seclists.org/bugtraq/2019/Sep/7
https://usn.ubuntu.com/3935-1/Third Party Advisory
http://packetstormsecurity.com/files/154361/Cisco-Device-Hardcoded-Credentials-GNU-glibc-BusyBox.html
http://seclists.org/fulldisclosure/2019/Sep/7
https://bugs.busybox.net/show_bug.cgi?id=11506Exploit, Issue Tracking, Third Party Advisory
https://busybox.net/news.htmlRelease Notes, Third Party Advisory
https://git.busybox.net/busybox/commit/?id=6d3b4bb24da9a07c263f3c1acf8df85382ff562cPatch, Third Party Advisory
https://seclists.org/bugtraq/2019/Sep/7
https://usn.ubuntu.com/3935-1/Third Party Advisory

Timeline

Published: Jan 9, 2019
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2018-20679?

How severe is CVE-2018-20679?

CVE-2018-20679 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 7.90% probability of exploitation in the next 30 days.

How do I fix CVE-2018-20679?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2018-20679?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST