CVE-2018-20679
Published: August 31, 2023Last modified: July 22, 2025
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.
Severity score breakdown
| Parameter | Value | 
|---|---|
| Base score | 7.5 | 
| Attack Vector | NETWORK | 
| Attack complexity | LOW | 
| Privileges required | NONE | 
| User interaction | NONE | 
| Scope | UNCHANGED | 
| Confidentiality | HIGH | 
| Integrity impact | NONE | 
| Availability impact | NONE | 
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N | 
Status
| Product | Release | Package | Status | 
|---|---|---|---|
| Alpaquita Linux | 23 LTS | busybox | Not affected (1.35.0-r30) | 
| Stream | busybox | Not affected (1.36.1-r6) | |
| Hardened Containers | 23 LTS | busybox | Not affected (1.35.0-r30) | 
| Stream | busybox | Not affected (1.36.1-r6) | 
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=11506
 - https://busybox.net/news.html
 - https://git.busybox.net/busybox/commit/?id=6d3b4bb24da9a07c263f3c1acf8df85382ff562c
 - https://seclists.org/bugtraq/2019/Sep/7
 - https://usn.ubuntu.com/3935-1/