BusyBox up to 1.29.x udhcp common.c udhcp_get_option DHCP Message out-of-bounds

Summaryinfo

A vulnerability has been found in BusyBox up to 1.29.x and classified as problematic. This impacts the function udhcp_get_option of the file networking/udhcp/common.c of the component udhcp. This manipulation as part of DHCP Message causes out-of-bounds. The identification of this vulnerability is CVE-2018-20679. The attack needs to be done within the local network. There is no exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability has been found in BusyBox up to 1.29.x and classified as problematic. Affected by this vulnerability is the function udhcp_get_option of the file networking/udhcp/common.c of the component udhcp. The manipulation as part of a DHCP Message leads to a out-of-bounds vulnerability. The CWE definition for the vulnerability is CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality. The summary by CVE is:

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.

The bug was discovered 01/08/2019. The weakness was shared 01/09/2019 by Matt (Website). The advisory is shared at bugs.busybox.net. This vulnerability is known as CVE-2018-20679 since 01/09/2019. The attack needs to be done within the local network. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available.

The vulnerability was handled as a non-public zero-day exploit for at least 1 days. During that time the estimated underground price was around $0-$5k. The commercial vulnerability scanner Qualys is able to test this issue with plugin 197418 (Ubuntu Security Notification for Busybox Vulnerabilities (USN-3935-1)).

Upgrading to version 1.30.0 eliminates this vulnerability.

The vulnerability is also documented in the databases at EUVD (EUVD-2018-13227) and SecurityFocus (BID 72324†). The entries VDB-96755, VDB-96756, VDB-97860 and VDB-104922 are related to this item. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

• BusyBox

Version

• 1.0
• 1.1
• 1.2
• 1.3
• 1.4
• 1.5
• 1.6
• 1.7
• 1.8
• 1.9
• 1.10
• 1.11
• 1.12
• 1.13
• 1.14
• 1.15
• 1.16
• 1.17
• 1.18
• 1.19
• 1.20
• 1.21
• 1.22
• 1.23
• 1.24
• 1.25
• 1.26
• 1.27
• 1.28
• 1.29

License

• open-source

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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