How severe is CVE-2019-6820?

CVE-2019-6820 has a CVSS 3.x base score of 8.2, 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 low, and availability high.

Is CVE-2019-6820 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-6820?

CVE-2019-6820 primarily affects Schneider-electric Modicon M100 Firmware. In total, 12 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-6820?

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-2019-6820 published?

CVE-2019-6820 was published on 2019-05-22 and last updated on 2026-06-17.

CVE-2019-6820

CVE-2019-6820 is a high-severity vulnerability in Schneider-electric Modicon M100 Firmware with a CVSS 3.x base score of 8.2. 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-306.

Key facts

Severity: High (CVSS 3.x base score 8.2)
CVSS v2: 6.4
EPSS exploit prediction: 1% (66th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-306
Affected product: Schneider-electric Modicon M100 Firmware
Published: 2019-05-22
Last modified: 2026-06-17

Description

A CWE-306: Missing Authentication for Critical Function vulnerability exists which could cause a modification of device IP configuration (IP address, network mask and gateway IP address) when a specific Ethernet frame is received in all versions of: Modicon M100, Modicon M200, Modicon M221, ATV IMC drive controller, Modicon M241, Modicon M251, Modicon M258, Modicon LMC058, Modicon LMC078, PacDrive Eco ,PacDrive Pro, PacDrive Pro2

Frequently asked questions

What is CVE-2019-6820?: A CWE-306: Missing Authentication for Critical Function vulnerability exists which could cause a modification of device IP configuration (IP address, network mask and gateway IP address) when a specific Ethernet frame is received in all versions of: Modicon M100, Modicon M200, Modicon M221, ATV IMC drive controller, Modicon M241, Modicon M251, Modicon M258, Modicon LMC058, Modicon LMC078, PacDrive Eco ,PacDrive Pro, PacDrive Pro2
How severe is CVE-2019-6820?: CVE-2019-6820 has a CVSS 3.x base score of 8.2, 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 low, and availability high.
Is CVE-2019-6820 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-6820?: CVE-2019-6820 primarily affects Schneider-electric Modicon M100 Firmware. In total, 12 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-6820?: 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-2019-6820 published?: CVE-2019-6820 was published on 2019-05-22 and last updated on 2026-06-17.

References

https://www.schneider-electric.com/en/download/document/SEVD-2019-134-02/

Affected products (12)

cpe:2.3:o:schneider-electric:modicon_m100_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:modicon_m200_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:modicon_m221_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:atv_imc_drive_controller_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:modicon_m241_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:modicon_m251_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:modicon_m258_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:modicon_lmc058_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:modicon_lmc078_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:pacdrive_eco_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:pacdrive_pro_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:pacdrive_pro2_firmware:*:*:*:*:*:*:*:*

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