CVE-2018-20679
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (7.69%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- EPSS
- 7.69% probability · 95th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-125
- Affected
- busybox/busybox · canonical/ubuntu linux
- Source
- cve@mitre.org
EPSS 7.7% since 27 October 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
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
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.