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» CVE-2020-7566
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.
NVD Status： Modified ，CVE State: published
Threat Intelligence & Risk Assessment for CVE-2020-7566
Conclusion & alert: CVE-2020-7566 is rated Low Risk (33.3/100) : CVSS High severity, with low exploitation likelihood (EPSS 0.04%).Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
Exploit prediction scoring system (EPSS) score for CVE-2020-7566
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
#
Date
Old EPSS score
New EPSS score
Delta (New - Old)
1
2026-03-02
0.05%
0.04%
-0.01%
2
2025-11-21
0.04%
0.05%
+0.01%
3
2025-11-18
—
0.04%
—
Full EPSS history
(10 records total)
Common vulnerability scoring system (CVSS) metrics for CVE-2020-7566
CVSS metrics for this CVE.
Base score
Version
Severity
Vector
Exploitability
Impact
Score source
7.3
3.1
HIGH
CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N
Click to expand
Attack vector (AV:A)
Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
2.1
5.2
[email protected]
7.1
3.1
HIGH
CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
Click to expand
Attack vector (AV:A)
Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.2
5.9
134c704f-9b21-4f2e-91b3-4a467353bcc0
4.3
2.0
MEDIUM
AV:A/AC:M/Au:N/C:P/I:P/A:N
Click to expand
Access vector (AV:A)
Requires access to an adjacent network segment.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
5.5
4.9
[email protected]
Weakness enumeration for CVE-2020-7566
GitHub Security Advisory for CVE-2020-7566
GHSA-j9h7-v335-8gcp · Severity: high
— A CWE-334: Small Space of Random Values vulnerability exists in Modicon M221 (all references, all...
Affected software / configurations for CVE-2020-7566
References for CVE-2020-7566
cvelogic
Threat Intelligence