Vulnerability 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.
CVSS Score
HIGH
Related Weaknesses (CWE)
References
- https://busybox.net/
- https://github.com/vda-linux/busybox_mirror/commit/42202bfb1e6ac51fa995beda8be4d
- https://github.com/vda-linux/busybox_mirror/commit/d368f3f7836d1c2484c8f839316e5
- https://www.vulncheck.com/advisories/busybox-dhcpv6-client-heap-buffer-overflow-
- https://y637f9qq2x.com/posts/busybox-dhcpv6-heap-overflow/
FAQ
What is CVE-2026-29004?
CVE-2026-29004 is a vulnerability with a CVSS score of 8.1 (HIGH). 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 attack...
How severe is CVE-2026-29004?
CVE-2026-29004 has been rated HIGH with a CVSS base score of 8.1/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-29004?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.