CVE-2019-5185
CWE-787Published: March 23, 2020· Updated: Jun 17, 2026
Official Description
An exploitable stack buffer overflow vulnerability vulnerability exists in the iocheckd service "I/O-Check" functionality of WAGO PFC 200. An attacker can send a specially crafted packet to trigger the parsing of this cache file. At 0x1ea28 the extracted state value from the xml file is used as an argument to /etc/config-tools/config_interfaces interface=X1 state=<contents of state node> using sprintf(). The destination buffer sp+0x40 is overflowed with the call to sprintf() for any state values that are greater than 512-len("/etc/config-tools/config_interfaces interface=X1 state=") in length. Later, at 0x1ea08 strcpy() is used to copy the contents of the stack buffer that was overflowed sp+0x40 into sp+0x440. The buffer sp+0x440 is immediately adjacent to sp+0x40 on the stack. Therefore, there is no NULL termination on the buffer sp+0x40 since it overflowed into sp+0x440. The strcpy() will result in invalid memory access. An state value of length 0x3c9 will cause the service to crash.
Technical Analysis
CVE-2019-5185 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 7.0.
From a weakness classification perspective (CWE-787): Out-of-bounds write vulnerabilities can lead to data corruption, crashes, or arbitrary code execution.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (2)
Quick Facts
Related CVEs (CWE-787)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2019-5185 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts