CVE-2026-29004

BusyBox DHCPv6 Client Heap Buffer Overflow via DNS_SERVERS

Published May 4, 2026 CVSS 4.0 · 7.2 High EPSS < 1% KEV · Not listed
Description
BusyBox before commit 42202bf contains a heap buffer overflow vulnerability in the DHCPv6 client (udhcpc6) DNS_SERVERS option handler in networking/udhcp/d6_dhcpc.c that allows network-adjacent attackers to trigger memory corruption by sending a crafted DHCPv6 response with a malformed D6_OPT_DNS_SERVERS option. Attackers can exploit incorrect heap buffer allocation calculations in the option_to_env() function to cause denial of service or achieve arbitrary code execution on embedded systems without heap hardening.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Vda-linux
Vda-linux busybox Mirror
Vendors & Products Vda-linux
Vda-linux busybox Mirror
Type Values Removed Values Added
Description BusyBox before commit 42202bf contains a heap buffer overflow vulnerability in the DHCPv6 client (udhcpc6) DNS_SERVERS option handler in networking/udhcp/d6_dhcpc.c that allows network-adjacent attackers to trigger memory corruption by sending a crafted DHCPv6 response with a malformed D6_OPT_DNS_SERVERS option. Attackers can exploit incorrect heap buffer allocation calculations in the option_to_env() function to cause denial of service or achieve arbitrary code execution on embedded systems without heap hardening.
Title BusyBox DHCPv6 Client Heap Buffer Overflow via DNS_SERVERS
Weaknesses CWE-122
References
Metrics cvssV3_1

{'score': 8.1, 'vector': 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H'}

cvssV4_0

{'score': 7.2, 'vector': 'CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Jul 15, 2026, 1:10 AM
Reserved
Mar 3, 2026, 4:42 PM
Status
Awaiting Analysis
Published
May 4, 2026, 6:16 PM
Modified
Oct 26, 2026, 7:10 PM