CVE-2021-37740 json
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 b…
published 2022-04-20 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-24221
- cvss
- 7.5
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 4.6%
- EPSS 4.6% chance of exploitation in 30 days, percentile 91%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- mdt scn-ip000.03_firmware 3.0.4
- mdt scn-ip100.03_firmware 3.0.4
Exploit prediction
4.62% chance of exploitation in the next 30 days, higher than 91% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/robertguetzkow/CVE-2021-37740 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 7.8 | AV:N/AC:L/Au:N/C:N/I:N/A:C |
References
-
github.com
/robertguetzkow/CVE-2021-37740
exploit, release-notes, third-party-advisory
-
mdt.de
/download/MDT_CL_SCN_IP_03_IP_Interface_Router.pdf
release-notes, vendor-advisory
-
mdt.de
/EN_IP_Interface_Router.html
broken-link
Sources
- CVE List CVE-2021-37740
- NVD CVE-2021-37740
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