How severe is CVE-2019-6819?

CVE-2019-6819 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-2019-6819 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-6819?

CVE-2019-6819 primarily affects Schneider-electric Modicon M340 Firmware. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-6819?

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-2019-6819 published?

CVE-2019-6819 was published on 2019-05-22 and last updated on 2026-06-17.

CVE-2019-6819

CVE-2019-6819 is a high-severity vulnerability in Schneider-electric Modicon M340 Firmware 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-754.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (62nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-754
Affected product: Schneider-electric Modicon M340 Firmware
Published: 2019-05-22
Last modified: 2026-06-17

Description

A CWE-754: Improper Check for Unusual or Exceptional Conditions vulnerability exists which could cause a possible Denial of Service when specific Modbus frames are sent to the controller in the products: Modicon M340 - firmware versions prior to V3.01, Modicon M580 - firmware versions prior to V2.80, All firmware versions of Modicon Quantum and Modicon Premium.

Frequently asked questions

What is CVE-2019-6819?: A CWE-754: Improper Check for Unusual or Exceptional Conditions vulnerability exists which could cause a possible Denial of Service when specific Modbus frames are sent to the controller in the products: Modicon M340 - firmware versions prior to V3.01, Modicon M580 - firmware versions prior to V2.80, All firmware versions of Modicon Quantum and Modicon Premium.
How severe is CVE-2019-6819?: CVE-2019-6819 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-2019-6819 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-6819?: CVE-2019-6819 primarily affects Schneider-electric Modicon M340 Firmware. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-6819?: 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-2019-6819 published?: CVE-2019-6819 was published on 2019-05-22 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:o:schneider-electric:modicon_m340_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:modicon_m580_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:modicon_quantum_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:modicon_premium_firmware:*:*:*:*:*:*:*:*

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