{"id":"CVE-2026-29004","state":"PUBLISHED","title":"BusyBox DHCPv6 Client Heap Buffer Overflow via DNS_SERVERS","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. 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A heap buffer overflow vulnerability exists in the Dynamic Host Configuration Protocol version 6 (DHCPv6) client, specifically within the `option_to_env()` function. Network-adjacent attackers can exploit this by sending a crafted DHCPv6 response containing a malformed D6_OPT_DNS_SERVERS option. 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If the DHCPv6 client functionality is not essential for the system's operation, consider disabling the `udhcpc6` service or configuring it to only accept responses from known, trusted sources. Consult product-specific documentation for details on managing network services and configurations. Any changes to network service configurations may require a service restart to take effect, potentially impacting network connectivity."}],"x_adpType":"supplier","x_generator":{"engine":"sadp-cli 1.0.0"}}]}}}