A Permissions, Privileges, and Access Control vulnerability exists in Schneider Electric's Modicon M221 product (all references, all versio…

Published 8 y ago 2018-08-29 · modified 4 mo ago 2026-06-17 · JSON

CVSS

9.8

v3.1 · CNA

CISA KEV

not known exploited

EPSS

1.9%

percentile 79%

Public exploits

none known

A Permissions, Privileges, and Access Control vulnerability exists in Schneider Electric's Modicon M221 product (all references, all versions prior to firmware V1.6.2.0). The vulnerability allows unauthorized users to overwrite the original password with their password. If an attacker exploits this vulnerability and overwrite the password, the attacker can upload the original program from the PLC.

CISA SSVC assessment

Exploitation: none
Automatable: yes
Technical impact: total
Assessed: 5 mo ago 2026-05-29

Exploit prediction (EPSS)

1.87% probability of exploitation in the next 30 days, higher than 79% of all scored CVEs.

CVSS scores

Assigned by	Version	Score	Vector
CISA ADP	3.1	9.8	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`
NVD	3.1	9.8	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`
CNA	3.1	9.8	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`
NVD	2.0	7.5	`AV:N/AC:L/Au:N/C:P/I:P/A:P`

Affected products

Schneider Electric SE Modicon M221, all references, all versions prior to firmware V1.6.2.0

Classification

Weakness

CWE-284 Improper Access Control
CWE-287 Improper Authentication

References

securityfocus.com /bid/105182 · vdb-entry, x_refsource_BID, x_transferred
schneider-electric.com /en/download/document/SEVD-2018-235-01/ · x_refsource_CONFIRM, x_transferred

Sources

CVE List: CVE-2018-7791
NVD: CVE-2018-7791

vulnwire keeps one entry per vulnerability: the CVE id wins, then GHSA; records that alias each other are merged. Machine-readable: JSON.

Summary