CVE-2019-5186
Severity CVSS v4.0:
Pending analysis
Type:
CWE-120
Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
Publication date:
23/03/2020
Last modified:
21/07/2021
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 0x1eb9c the extracted interface element name from the xml file is used as an argument to /etc/config-tools/config_interfaces interface= using sprintf(). The destination buffer sp+0x40 is overflowed with the call to sprintf() for any interface values that are greater than 512-len("/etc/config-tools/config_interfaces interface=") 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 interface value of length 0x3c4 will cause the service to crash.
Impact
Base Score 3.x
7.00
Severity 3.x
HIGH
Base Score 2.0
4.40
Severity 2.0
MEDIUM
Vulnerable products and versions
| CPE | From | Up to |
|---|---|---|
| cpe:2.3:o:wago:pfc200_firmware:03.02.02\(14\):*:*:*:*:*:*:* | ||
| cpe:2.3:h:wago:pfc200:-:*:*:*:*:*:*:* |
To consult the complete list of CPE names with products and versions, see this page