How severe is CVE-2020-7559?

CVE-2020-7559 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2020-7559 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-7559?

CVE-2020-7559 affects Schneider-electric Ecostruxure Control Expert. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-7559?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2020-7559 published?

CVE-2020-7559 was published on 2020-11-19 and last updated on 2026-06-17.

CVE-2020-7559

CVE-2020-7559 is a high-severity vulnerability in Schneider-electric Ecostruxure Control Expert with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-120.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (77th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-120
Affected product: Schneider-electric Ecostruxure Control Expert
Published: 2020-11-19
Last modified: 2026-06-17

Description

A CWE-120: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') vulnerability exists in PLC Simulator on EcoStruxureª Control Expert (now Unity Pro) (all versions) that could cause a crash of the PLC simulator present in EcoStruxureª Control Expert software when receiving a specially crafted request over Modbus.

Frequently asked questions

What is CVE-2020-7559?: A CWE-120: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') vulnerability exists in PLC Simulator on EcoStruxureª Control Expert (now Unity Pro) (all versions) that could cause a crash of the PLC simulator present in EcoStruxureª Control Expert software when receiving a specially crafted request over Modbus.
How severe is CVE-2020-7559?: CVE-2020-7559 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2020-7559 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-7559?: CVE-2020-7559 affects Schneider-electric Ecostruxure Control Expert. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-7559?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-7559 published?: CVE-2020-7559 was published on 2020-11-19 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:schneider-electric:ecostruxure_control_expert:*:*:*:*:*:*:*:*

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