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CVE-2021-37740

Status: ModifiedHigh (7.5)—PoC
Severity7.5High · CVSS 3.1
Exploitation probability4.62 %higher than 92% of CVEs
Active exploitationNonot in the CISA catalog
Public exploitAvailableProof of concept on GitHub (unverified)

A denial of service vulnerability exists in MDT's firmware for the KNXnet/IP Secure router SCN-IP100.03 and KNX IP interface SCN-IP000.03 before v3.0.4, that allows a remote attacker to turn the device unresponsive to all requests on the KNXnet/IP Secure layer, until the device is rebooted, via a SESSION_REQUEST frame with a modified total length field.

CVSS

Base score
7.5
Version
3.1
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days
4.62 %
Percentile among all scored CVEs
92
Score date
10/21/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Public exploits

Exploit code or detection templates are publicly available. This is not the same as confirmed active exploitation (KEV), but it raises the risk: patch with priority.

⚠️ GitHub proofs of concept are not verified: some are fake or contain malware. Never run them outside an isolated lab.

Affected technologies (2)

MDT — Scn-ip000.03 FirmwareMDT — Scn-ip100.03 Firmware

CWEs

References

Show 6 references

Raw JSON (NVD)

Show
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    },
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      "lang": "es",
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