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
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| vda-linux | busybox_mirror | — | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | busybox | No fix yet | — |
| Debian 13 | busybox | No fix yet | — |
| Debian 12 | busybox | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | busybox | No fix yet | — |
| Ubuntu 26.04 LTS | busybox | No fix yet | — |
| Ubuntu 25.10 | busybox | No fix yet | — |
| Ubuntu 24.04 LTS | busybox | No fix yet | — |
| Ubuntu 22.04 LTS | busybox | No fix yet | — |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | busybox | No fix yet | — |
| Ubuntu Pro 18.04 LTS | busybox | No fix yet | — |
| Ubuntu Pro 16.04 LTS | busybox | No fix yet | — |
| Ubuntu Pro 14.04 LTS | busybox | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Hardened Images 1 | busybox +2 | 1.37.0-7.3.hum1 | RHSA-2026:30652 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | busybox | 1.37.0-160000.6.1 | SUSE-SU-2026:22020-1 |
| SLES 16.0 | busybox | 1.37.0-160000.6.1 | SUSE-SU-2026:22020-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | busybox | 1.37.0-11.1 | openSUSE-SU-2026:10740-1 |
Advisories 4
- RHSA-2026:30652 Red Hat Security Advisory: Red Hat Hardened Images RPMs Security Update Red Hat Security Advisories (RHSA) · Oct 6, 2026
- WID-SEC-2026-1356 BusyBox: Schwachstelle ermöglicht Codeausführung oder DoS BSI CERT-Bund (WID) · Jun 28, 2026
- SUSE-SU-2026:22020-1 Security update for busybox SUSE / openSUSE Security Updates · Jun 9, 2026
- openSUSE-SU-2026:10740-1 busybox-1.37.0-11.1 on GA media SUSE / openSUSE Security Updates · May 11, 2026
References
- https://y637f9qq2x.com/posts/busybox-dhcpv6-heap-overflow/ technical-description exploit
- https://github.com/vda-linux/busybox_mirror/commit/42202bfb1e6ac51fa995beda8be4d7b654aeee2a patch
- https://github.com/vda-linux/busybox_mirror/commit/d368f3f7836d1c2484c8f839316e5c93e76d4409 patch
- https://busybox.net/ product
- https://www.vulncheck.com/advisories/busybox-dhcpv6-client-heap-buffer-overflow-via-dns-servers third-party-advisory