← Vulnerability feed

Vulnerability record · CVE-2020-7566 · published 19 November 2020

CVE-2020-7566: Schneider-electric modicon m221 firmware vulnerability

Schneider Electric · Modicon M221 Firmware

A CWE-334: Small Space of Random Values vulnerability exists in Modicon M221 (all references, all versions) that could allow the attacker to break the encryption keys when the attacker has captured the traffic between EcoStruxure Machine - Basic software and Modicon M221 controller.

7.3 CVSS 3.1 High EPSS 0.30% · top 80.0% CWE-334 · CWE-334
7.3CVSS 3.1 base score, v2 4.3
0.30%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
4References
17 Jun 2026Last modified by NVD

Description

A CWE-334: Small Space of Random Values vulnerability exists in Modicon M221 (all references, all versions) that could allow the attacker to break the encryption keys when the attacker has captured the traffic between EcoStruxure Machine - Basic software and Modicon M221 controller.

CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://us-cert.cisa.gov/ics/advisories/icsa-20-343-04 Third Party AdvisoryUS Government Resource
https://www.se.com/ww/en/download/document/SEVD-2020-315-05/ Vendor Advisory
https://us-cert.cisa.gov/ics/advisories/icsa-20-343-04 Third Party AdvisoryUS Government Resource
https://www.se.com/ww/en/download/document/SEVD-2020-315-05/ Vendor Advisory

Track CVE-2020-7566 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

9.8CVE-2020-7489Schneider-electric ecostruxure machine expert injection vulnerabilityA CWE-74: Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') vulnerability exists on EcoStruxure Mach…EPSS 1.6%9.8CVE-2018-7790Schneider-electric modicon m221 firmware authentication bypass by capture-replay vulnerabilityAn Information Management Error vulnerability exists in Schneider Electric's Modicon M221 product (all references, all versions prior to firmware V1.…EPSS 2.5%9.8CVE-2018-7791Schneider-electric modicon m221 firmware improper authentication vulnerabilityA Permissions, Privileges, and Access Control vulnerability exists in Schneider Electric's Modicon M221 product (all references, all versions prior t…EPSS 1.9%8.2CVE-2019-6820Schneider-electric modicon m100 firmware missing authentication for critical function vulnerabilityA CWE-306: Missing Authentication for Critical Function vulnerability exists which could cause a modification of device IP configuration (IP address,…EPSS 1.3%7.5CVE-2018-7821Schneider-electric somachine basic allocation without limits vulnerabilityAn Environment (CWE-2) vulnerability exists in SoMachine Basic, all versions, and Modicon M221(all references, all versions prior to firmware V1.10.0…EPSS 1.1%7.5CVE-2019-10953Abb pm554-tp-eth firmware uncontrolled resource consumption vulnerabilityABB, Phoenix Contact, Schneider Electric, Siemens, WAGO - Programmable Logic Controllers, multiple versions. Researchers have found some controllers …EPSS 3.4%7.5CVE-2018-7792Schneider-electric modicon m221 firmware missing authorization vulnerabilityA Permissions, Privileges, and Access Control vulnerability exists in Schneider Electric's Modicon M221 product (all references, all versions prior t…EPSS 1.1%7.5CVE-2018-7789Schneider-electric modicon m221 firmware vulnerabilityAn Improper Check for Unusual or Exceptional Conditions vulnerability exists in Schneider Electric's Modicon M221 product (all references, all versio…EPSS 2.8%

Source: NIST National Vulnerability Database (record CVE-2020-7566), CISA KEV, FIRST EPSS (scores of 2026-09-28). This page is refreshed as NVD updates the record.