CVE-2019-10121 json
eQ-3 HomeMatic CCU2 devices before 2.41.8 and CCU3 devices before 3.43.15 use session IDs for authentication but lack authorization checks.
published 2019-07-10 7 y ago modified 2026-06-17 4 mo ago also EUVD-2019-2163
- cvss
- 9.8
- version 3.0, 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
eQ-3 HomeMatic CCU2 devices before 2.41.8 and CCU3 devices before 3.43.15 use session IDs for authentication but lack authorization checks. An attacker can obtain a session ID via the user authentication dialogue, aka HMCCU-153. This leads to automatic login as admin.
Patch / fix
- eq-3 ccu3_firmware 3.43.15
- eq-3 ccu2_firmware 2.41.8
Exploit prediction
4.63% chance of exploitation in the next 30 days, higher than 91% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.0 | 9.8 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 7.5 | AV:N/AC:L/Au:N/C:P/I:P/A:P |
Classification
- Weakness
-
- CWE-306 Missing Authentication for Critical Functionality
References
-
eq-3.de
/Downloads/Software/HM-CCU2-Firmware_Updates/HM-CCU-2.41.9/HM-CCU2-Changelog.2.41.9.pdf
release-notes, vendor-advisory
-
eq-3.de
/Downloads/Software/CCU3-Firmware/CCU3-3.43.16/CCU3-Changelog.3.43.16.pdf
release-notes, vendor-advisory
-
os-s.de
/advisories/OSS-2018-01.pdf
broken-link
Sources
- CVE List CVE-2019-10121
- NVD CVE-2019-10121
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