How severe is CVE-2019-6843?

CVE-2019-6843 has a CVSS 3.x base score of 4.9, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2019-6843 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-6843?

CVE-2019-6843 primarily affects Schneider-electric Modicon M580 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-2019-6843?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2019-6843 published?

CVE-2019-6843 was published on 2019-10-29 and last updated on 2026-06-17.

CVE-2019-6843

CVE-2019-6843 is a medium-severity vulnerability in Schneider-electric Modicon M580 Firmware with a CVSS 3.x base score of 4.9. 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-755.

Key facts

Severity: Medium (CVSS 3.x base score 4.9)
CVSS v2: 4.0
EPSS exploit prediction: 1% (57th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-755
Affected product: Schneider-electric Modicon M580 Firmware
Published: 2019-10-29
Last modified: 2026-06-17

Description

A CWE-755: Improper Handling of Exceptional Conditions vulnerability exists in Modicon M580 with firmware (version prior to V3.10), Modicon M340 (all firmware versions), and Modicon BMxCRA and 140CRA modules (all firmware versions), which could cause a Denial of Service attack on the PLC when upgrading the controller with an empty firmware package using FTP protocol.

Frequently asked questions

What is CVE-2019-6843?: A CWE-755: Improper Handling of Exceptional Conditions vulnerability exists in Modicon M580 with firmware (version prior to V3.10), Modicon M340 (all firmware versions), and Modicon BMxCRA and 140CRA modules (all firmware versions), which could cause a Denial of Service attack on the PLC when upgrading the controller with an empty firmware package using FTP protocol.
How severe is CVE-2019-6843?: CVE-2019-6843 has a CVSS 3.x base score of 4.9, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2019-6843 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-6843?: CVE-2019-6843 primarily affects Schneider-electric Modicon M580 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-2019-6843?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2019-6843 published?: CVE-2019-6843 was published on 2019-10-29 and last updated on 2026-06-17.

References

https://www.se.com/ww/en/download/document/SEVD-2019-281-02/

Affected products (4)

cpe:2.3:o:schneider-electric:modicon_m580_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:modicon_m340_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:modicon_bmxcra_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:modicon_140cra_firmware:*:*:*:*:*:*:*:*

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