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.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
vda-linux busybox_mirror
Default version status: affected
0 to < 42202bfb1e6ac51fa995beda8be4d7b654aeee2aaffected
References
- https://y637f9qq2x.com/posts/busybox-dhcpv6-heap-overflow/ ↗
- https://github.com/vda-linux/busybox_mirror/commit/42202bfb1e6ac51fa995beda8be4d7b654aeee2a ↗
- https://github.com/vda-linux/busybox_mirror/commit/d368f3f7836d1c2484c8f839316e5c93e76d4409 ↗
- https://busybox.net/ ↗
- https://www.vulncheck.com/advisories/busybox-dhcpv6-client-heap-buffer-overflow-via-dns-servers ↗
- https://access.redhat.com/security/cve/CVE-2026-29004 ↗
- https://bugzilla.redhat.com/show_bug.cgi?id=2466526 ↗
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-29004.json ↗
- https://access.redhat.com/errata/RHSA-2026:30652 ↗