A Insufficient Verification of Data Authenticity (CWE-345) vulnerability exists in the Modicon M221, all versions, which could cause a chan…

published 2018-11-02 8 y ago modified 2026-06-17 4 mo ago also EUVD-2018-19510

cvss: 8.2; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.7%; EPSS 0.7% chance of exploitation in 30 days, percentile 51%
public exploits: 0; none known

A Insufficient Verification of Data Authenticity (CWE-345) vulnerability exists in the Modicon M221, all versions, which could cause a change of IPv4 configuration (IP address, mask and gateway) when remotely connected to the device.

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

cisa ICSA-18-324-02 updated 2018-11-20 cvss 8.2

Schneider Electric Modicon M221

Schneider Electric Software, LLC Modicon M221
affected: vendor fix, mitigation “Set up a firewall blocking all remote/external access to Port 502.” schneider-electric.com

From CISA ICS and IT advisories (CSAF, https://github.com/cisagov/CSAF), a U.S. Government work; changed: reduced to products, statuses and remediations. CISA notification · csaf

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 5 mo ago (2026-05-29)

Exploit prediction

0.66% chance of exploitation in the next 30 days, higher than 51% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CISA ADP	3.1	8.2	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L
NVD	3.1	8.2	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L
CNA	3.1	8.2	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L
NVD	2.0	6.4	AV:N/AC:L/Au:N/C:N/I:P/A:P

Affected products

Schneider Electric SE Modicon M221, All Versions

Classification

Weakness

CWE-345 Insufficient Verification of Data Authenticity

References

schneider-electric.com /en/download/document/SEVD-2018-270-01/
mitigation, vendor-advisory
securityfocus.com /bid/105970
vdb-entry, third-party-advisory

Sources

CVE List CVE-2018-7798
NVD CVE-2018-7798

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary