How severe is CVE-2019-6811?

CVE-2019-6811 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-2019-6811 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-6811?

CVE-2019-6811 primarily affects Schneider-electric Modicon Quantum 140noe77101 Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-6811?

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-2019-6811 published?

CVE-2019-6811 was published on 2019-09-17 and last updated on 2026-06-17.

CVE-2019-6811

CVE-2019-6811 is a high-severity vulnerability in Schneider-electric Modicon Quantum 140noe77101 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% (67th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-754
Affected product: Schneider-electric Modicon Quantum 140noe77101 Firmware
Published: 2019-09-17
Last modified: 2026-06-17

Description

An Improper Check for Unusual or Exceptional Conditions (CWE-754) vulnerability exists in Modicon Quantum 140 NOE771x1 version 6.9 and earlier, which could cause denial of service when the module receives an IP fragmented packet with a length greater than 65535 bytes. The module then requires a power cycle to recover.

Frequently asked questions

What is CVE-2019-6811?: An Improper Check for Unusual or Exceptional Conditions (CWE-754) vulnerability exists in Modicon Quantum 140 NOE771x1 version 6.9 and earlier, which could cause denial of service when the module receives an IP fragmented packet with a length greater than 65535 bytes. The module then requires a power cycle to recover.
How severe is CVE-2019-6811?: CVE-2019-6811 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-2019-6811 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-6811?: CVE-2019-6811 primarily affects Schneider-electric Modicon Quantum 140noe77101 Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-6811?: 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-2019-6811 published?: CVE-2019-6811 was published on 2019-09-17 and last updated on 2026-06-17.

References

https://www.schneider-electric.com/en/download/document/SEVD-2019-253-02/

Affected products (2)

cpe:2.3:o:schneider-electric:modicon_quantum_140noe77101_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:modicon_quantum_140noe77111_firmware:*:*:*:*:*:*:*:*

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