ConnMan through 2.0 has a stack-based buffer overflow via a DHCPv6 Reply message. This occurs in get_domains in gdhcp/client.c. It copies a fixed NS_MAXDNAME (1025) bytes from a DHCPv6 DOMAIN_LIST (option 24) value into a 1026-byte stack buffer dns_name regardless of the actual option length, then walks DNS labels with an unbounded "c += jump + 1" loop. A crafted DHCPv6 REPLY with a DOMAIN_LIST option of >= 1025 non-zero bytes makes the label walk leave the buffer and read/write '.' past its end in attacker-chosen strides. An on-link attacker can trigger this without authentication via a forged Router Advertisement (O=1) and a forged DHCPv6 REPLY matching xid/CLIENTID with a long DOMAIN_LIST. The impact is unauthenticated on-link crash of connmand (runs as root). This was introduced in bb06c47.

In ConnMan through 1.44, parse_rr in dnsproxy.c has a memcpy length that depends on an RR RDLENGTH value, i.e., *rdlen=ntohs(rr->rdlen) and memcpy(response+offset,*end,*rdlen) without a check for whether the sum of *end and *rdlen exceeds max. Consequently, *rdlen may be larger than the amount of remaining packet data in the current state of parsing. Values of stack memory locations may be sent over the network in a response.

In ConnMan through 1.44, the lookup string in ns_resolv in dnsproxy.c can be NULL or an empty string when the TC (Truncated) bit is set in a DNS response. This allows attackers to cause a denial of service (application crash) or possibly execute arbitrary code, because those lookup values lead to incorrect length calculations and incorrect memcpy operations.

ConnMan before 0.85 does not ensure that netlink messages originate from the kernel, which allows remote attackers to bypass intended access restrictions and cause a denial of service via a crafted netlink message.

The loopback plug-in in ConnMan before 0.85 allows remote attackers to execute arbitrary commands via shell metacharacters in the (1) host name or (2) domain name in a DHCP reply.

Integer overflow in the dhcpv6_get_option function in gdhcp/client.c in ConnMan before 0.85 allows remote attackers to cause a denial of service (infinite loop and crash) via an invalid length value in a DHCP packet.