CVE-2023-28488: Intel ConnMan Buffer Overflow Vulnerability

CVE-2023-28488 Overview

CVE-2023-28488 is a stack-based buffer overflow vulnerability in the gdhcp component of Intel ConnMan through version 1.41. The vulnerability exists in client.c and can be exploited by network-adjacent attackers operating a crafted DHCP server to cause a denial of service condition, terminating the connman process.

Critical Impact
Network-adjacent attackers can crash the ConnMan service through malicious DHCP responses, disrupting network connectivity management on affected systems.

Affected Products

Intel ConnMan versions through 1.41
Linux distributions using ConnMan for network management
Embedded systems and IoT devices utilizing ConnMan

Discovery Timeline

April 12, 2023 - CVE-2023-28488 published to NVD
February 8, 2025 - Last updated in NVD database

Technical Details for CVE-2023-28488

Vulnerability Analysis

This vulnerability is classified as CWE-787 (Out-of-bounds Write), specifically manifesting as a stack-based buffer overflow in the DHCP client implementation. The flaw occurs when the gdhcp component processes specially crafted DHCP responses from a malicious server on the same network segment.

The attack requires the attacker to be on the adjacent network (typically the same local area network) and operate a rogue DHCP server. When a vulnerable ConnMan client requests network configuration via DHCP, the attacker's crafted response triggers the buffer overflow condition in the client processing code.

Root Cause

The root cause lies in improper bounds checking within client.c when handling DHCP option data. The code fails to adequately validate the length of incoming DHCP options before copying them to stack-allocated buffers, allowing an attacker to overflow the buffer with excessively long or malformed data.

Attack Vector

The attack is executed from an adjacent network position, requiring no authentication or user interaction. An attacker sets up a malicious DHCP server that responds to DHCP requests with crafted packets containing oversized or malformed option fields. When the vulnerable ConnMan client processes these responses, the stack buffer is overwritten, causing the connman process to crash and resulting in denial of service.

The vulnerability affects the availability of the network management service. While the immediate impact is process termination (denial of service), stack-based buffer overflows can potentially be leveraged for code execution in certain scenarios, though no such exploit has been publicly demonstrated for this specific vulnerability.

Detection Methods for CVE-2023-28488

Indicators of Compromise

Unexpected crashes or restarts of the connmand process
Multiple DHCP requests from the same client in short succession (indicating service restart attempts)
Abnormally large DHCP response packets on the network
Core dumps from the connman service showing stack corruption

Detection Strategies

Monitor for connman process crashes using systemd journal or syslog analysis
Implement network-based detection for malformed or oversized DHCP packets
Deploy intrusion detection rules to identify suspicious DHCP server responses
Use SentinelOne Singularity to detect anomalous process terminations and potential exploitation attempts

Monitoring Recommendations

Configure alerting on repeated connman service failures
Enable DHCP traffic logging at network boundaries
Monitor for unauthorized DHCP servers on internal network segments
Review system logs for segmentation faults in network management processes

How to Mitigate CVE-2023-28488

Immediate Actions Required

Update ConnMan to a patched version (versions after 1.41 with the security fix applied)
Apply vendor-supplied security patches from your Linux distribution
Consider network segmentation to limit exposure to adjacent network attacks
Implement DHCP snooping on network switches to prevent rogue DHCP servers

Patch Information

Intel has released a patch for this vulnerability. The fix is available in the ConnMan Patch Commit which addresses the buffer overflow in client.c.

Debian has also released security advisories for affected packages:

Workarounds

Enable DHCP snooping on managed switches to block unauthorized DHCP servers
Use static IP configuration where feasible to avoid DHCP dependency
Implement 802.1X network access control to limit network-adjacent attackers
Consider using alternative network management solutions if patching is not immediately possible

bash

# Example: Enable DHCP snooping on Cisco switches to mitigate rogue DHCP servers
ip dhcp snooping
ip dhcp snooping vlan 1-100
interface GigabitEthernet0/1
  ip dhcp snooping trust
  description Trusted DHCP Server Port