How severe is CVE-2019-6840?

CVE-2019-6840 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2019-6840 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-6840?

CVE-2019-6840 primarily affects Schneider-electric Meg6501-0001 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-2019-6840?

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

When was CVE-2019-6840 published?

CVE-2019-6840 was published on 2019-09-17 and last updated on 2026-06-17.

CVE-2019-6840

CVE-2019-6840 is a critical-severity vulnerability in Schneider-electric Meg6501-0001 Firmware with a CVSS 3.x base score of 9.8. 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-134.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 1% (63rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-134
Affected product: Schneider-electric Meg6501-0001 Firmware
Published: 2019-09-17
Last modified: 2026-06-17

Description

A Format String: CWE-134 vulnerability exists in U.motion Server (MEG6501-0001 - U.motion KNX server, MEG6501-0002 - U.motion KNX Server Plus, MEG6260-0410 - U.motion KNX Server Plus, Touch 10, MEG6260-0415 - U.motion KNX Server Plus, Touch 15), which could allow an attacker to send a crafted message to the target server, thereby causing arbitrary commands to be executed.

Frequently asked questions

What is CVE-2019-6840?: A Format String: CWE-134 vulnerability exists in U.motion Server (MEG6501-0001 - U.motion KNX server, MEG6501-0002 - U.motion KNX Server Plus, MEG6260-0410 - U.motion KNX Server Plus, Touch 10, MEG6260-0415 - U.motion KNX Server Plus, Touch 15), which could allow an attacker to send a crafted message to the target server, thereby causing arbitrary commands to be executed.
How severe is CVE-2019-6840?: CVE-2019-6840 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2019-6840 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-6840?: CVE-2019-6840 primarily affects Schneider-electric Meg6501-0001 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-2019-6840?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2019-6840 published?: CVE-2019-6840 was published on 2019-09-17 and last updated on 2026-06-17.

References

https://www.schneider-electric.com/ww/en/download/document/SEVD-2019-253-01

Affected products (4)

cpe:2.3:o:schneider-electric:meg6501-0001_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:meg6501-0002_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:meg6260-0410_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:meg6260-0415_firmware:*:*:*:*:*:*:*:*

More vulnerabilities in Schneider-electric Meg6501-0001 Firmware

CVE-2019-6837 — Critical (CVSS 9.1): A Server-Side Request Forgery (SSRF): CWE-918 vulnerability exists in U.motion Server (MEG6501-0001 - U.motion KNX…
CVE-2019-6839 — High (CVSS 8.8): A CWE-434: Unrestricted Upload of File with Dangerous Type vulnerability exists in U.motion Server (MEG6501-0001 -…
CVE-2019-6836 — High (CVSS 7.5): A CWE-863: Incorrect Authorization vulnerability exists in U.motion Server (MEG6501-0001 - U.motion KNX server,…
CVE-2019-6838 — Medium (CVSS 6.5): A CWE-863: Incorrect Authorization vulnerability exists in U.motion Server (MEG6501-0001 - U.motion KNX server,…
CVE-2019-6835 — Medium (CVSS 5.4): A Cross-Site Scripting (XSS) CWE-79 vulnerability exists in U.motion Server (MEG6501-0001 - U.motion KNX server,…

All CVEs affecting Schneider-electric Meg6501-0001 Firmware →

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