CVE-2019-5186

mediumpriority · track · 28EPSS 0.008 · 58 %ileDEEUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
0.85% (58th) EPSS
CVSS 4.4 · medium
Is it mine?
7 products
Check your exposure
Who says so?
4 sources
cnnvd · enisa_euvd · nvd · wago_psirt

EPSS · scored 2026-10-27

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.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

  • Fixedwago_psirt

    The I/O-Check service protocol is only needed during installation and commissioning, not during normal operations. It is highly recommended to disable the I/O-Check service after commissioning. This is the easiest and securest way to protect your device from the listed vulnerabilities. Regardless of the action described above, the vulnerabilities are expected to be fixed in FW16 Release in Q2/2020.

  • Mitigationwago_psirt

    * Disable I/O-Check service. * Restrict network access to the device. * Do not directly connect the device to the internet. * Disable unused TCP/UDP-ports.

02

cvss

Technical severity, 0–10. One row per scoring source.

7.0
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.4–7

v2.04.4mediumAV:L/AC:M/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 3.4 · impact 6.4
v3.17highCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 1 · impact 5.9
v3.17highCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · WAGO PSIRT DE
v3.16.4mediumCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-120USprimaryCWE-787USprimaryCWE-120US
04

affected products (7)

Products and version ranges known to be affected.

05

advisories (1)

Vendor and ecosystem advisories describing this.

  • VDE-2020-011WAGO: Multiple Vulnerabilities in I/O-Check Service2020-03-09csaf · wago_psirtDE

    An attacker needs an authorized login on the device in order to exploit the herein mentioned vulnerabilities. The reported vulnerabilities allow a local attacker with valid login credentials who is able to create files on the device to change the devices settings, e.g. default gateway address, time server etc. and potentially execute code.

06

also known as (3)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

cnnvdenisa_euvdnvdwago_psirtNVDCVE.orgMITRE
published 2020-03-23modified 2026-06-17
09

references (4)

External citations — patches, advisories, analysis.

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