CVE-2026-29004

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.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://busybox.net/
https://github.com/vda-linux/busybox_mirror/commit/42202bfb1e6ac51fa995beda8be4d7b654aeee2a
https://github.com/vda-linux/busybox_mirror/commit/d368f3f7836d1c2484c8f839316e5c93e76d4409
https://www.vulncheck.com/advisories/busybox-dhcpv6-client-heap-buffer-overflow-via-dns-servers
https://y637f9qq2x.com/posts/busybox-dhcpv6-heap-overflow/

Configurations

No configuration.

History

06 May 2026, 14:16

Type	Values Removed	Values Added
References		() https://y637f9qq2x.com/posts/busybox-dhcpv6-heap-overflow/ -

04 May 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-04 18:16

Updated : 2026-05-06 14:16

NVD link : CVE-2026-29004

Mitre link : CVE-2026-29004

CVE.ORG link : CVE-2026-29004

JSON object : View

Products Affected

No product.

CWE

CWE-122

Heap-based Buffer Overflow

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