CVE-2019-5186

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=<contents of interface element> 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.

CVSS v3.0 7.0 HIGH
CVSS v2.0 4.4 MEDIUM

7.0^/10

CVSS v3.0 : HIGH

Vector :

Exploitability : 1.0 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

4.4^/10

CVSS v2.0 : MEDIUM

Vector : AV:L/AC:M/Au:N/C:P/I:P/A:P

Exploitability : 3.4 / Impact : 6.4

Access Vector LOCAL

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://talosintelligence.com/vulnerability_reports/TALOS-2019-0966	Exploit Mitigation Third Party Advisory

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Configurations

Configuration 1 (hide)

AND

cpe:2.3:o:wago:pfc200_firmware:03.02.02\(14\):*:*:*:*:*:*:*

cpe:2.3:h:wago:pfc200:-:*:*:*:*:*:*:*

Information

Published : 2020-03-23 07:15

Updated : 2021-07-21 04:39

NVD link : CVE-2019-5186

Mitre link : CVE-2019-5186

JSON object : View

CWE

CWE-787

Out-of-bounds Write

CWE-120

Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

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Products Affected

wago

pfc200_firmware
pfc200

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