CVE-2019-5178 : Security Advisory and Response

A stack buffer overflow vulnerability in the 'I/O-Check' functionality of the iocheckd service in WAGO PFC 200 Firmware version 03.02.02(14) allows attackers to crash the service by sending a specially crafted packet.

Understanding CVE-2019-5178

What is CVE-2019-5178?

This CVE refers to a stack buffer overflow vulnerability in the iocheckd service of WAGO PFC 200 Firmware version 03.02.02(14).

The Impact of CVE-2019-5178

Exploiting this vulnerability can lead to a denial of service (DoS) condition by crashing the affected service.

Technical Details of CVE-2019-5178

Vulnerability Description

The vulnerability arises due to a stack buffer overflow in the 'I/O-Check' functionality of the iocheckd service in WAGO PFC 200 Firmware version 03.02.02(14).

Affected Systems and Versions

Product: WAGO PFC200
Vendor: Wago
Firmware Version: 03.02.02(14)

Exploitation Mechanism

Attackers can exploit this vulnerability by sending a specifically designed packet that triggers the parsing of a cache file.
The overflow occurs in the destination buffer sp+0x440 when the sprintf() function is called with a hostname value longer than 1024 minus the length of '/etc/config-tools/change_hostname hostname='.
If the length of the hostname value is 0x3fd, the service will crash.

Mitigation and Prevention

Immediate Steps to Take

Apply vendor-provided patches or updates to address the vulnerability.
Implement network segmentation to restrict access to vulnerable systems.

Long-Term Security Practices

Regularly update and patch all software and firmware to prevent known vulnerabilities.
Conduct security assessments and penetration testing to identify and remediate weaknesses.

Patching and Updates

Stay informed about security advisories from the vendor and apply patches promptly to secure the system.