CVE-2012-2322 in ConnMan
Summary
by MITRE
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.
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Analysis
by VulDB Data Team • 12/02/2021
The vulnerability identified as CVE-2012-2322 represents a critical integer overflow flaw within the ConnMan network management daemon version 0.84 and earlier. This issue resides in the dhcpv6_get_option function located in gdhcp/client.c, which processes dhcpv6 packets received from network clients. The flaw manifests when the daemon encounters a DHCPv6 packet containing an invalid length value in its option fields, creating a scenario where the integer overflow condition triggers subsequent system instability. The vulnerability falls under CWE-190, which specifically addresses integer overflow conditions that can lead to unpredictable behavior and system compromise. This weakness enables attackers to exploit the protocol handling mechanism through carefully crafted network traffic that manipulates the length fields within DHCPv6 options.
The technical execution of this vulnerability involves the manipulation of DHCPv6 packet structures where an attacker can craft packets with malformed length indicators that exceed the maximum value representable by the integer data type used in the processing function. When the dhcpv6_get_option function attempts to process these invalid length values, the integer overflow causes the loop counter or buffer size calculation to wrap around to an extremely large value, resulting in an infinite loop during packet processing. The system becomes trapped in this loop as it attempts to iterate through a buffer of impossibly large size, ultimately leading to resource exhaustion and daemon crash. This behavior directly maps to the ATT&CK technique T1499.002, which describes network denial of service attacks that target application availability through resource exhaustion.
The operational impact of CVE-2012-2322 extends beyond simple denial of service to potentially compromise the entire network connectivity management system on affected devices. When the ConnMan daemon crashes due to this vulnerability, network interfaces managed by the daemon may become unresponsive or fail to establish proper network connections, affecting the device's ability to connect to networks automatically. The vulnerability affects systems running ConnMan versions prior to 0.85, which were widely deployed in embedded systems, mobile devices, and network appliances that rely on automatic network configuration. Attackers can exploit this vulnerability remotely without requiring authentication, making it particularly dangerous in environments where network infrastructure is exposed to untrusted networks or where attackers can inject malicious DHCPv6 packets into network segments.
Mitigation strategies for this vulnerability require immediate patching of affected ConnMan installations to version 0.85 or later, which includes proper bounds checking and input validation for DHCPv6 packet processing. Network administrators should implement DHCPv6 filtering rules at network boundaries to prevent malformed packets from reaching vulnerable systems, particularly in scenarios where the network infrastructure lacks proper DHCPv6 packet validation. Additionally, system monitoring should be enhanced to detect abnormal daemon behavior or resource consumption patterns that may indicate exploitation attempts. The fix implemented in ConnMan 0.85 addresses the root cause by introducing proper integer overflow protection and length validation checks within the dhcpv6_get_option function, ensuring that malformed packet lengths are rejected rather than processed, thereby preventing the infinite loop condition that led to the crash. Organizations should also consider implementing network segmentation and access control measures to limit exposure of vulnerable systems to untrusted network segments where malicious DHCPv6 packets might originate.