eQ-3 HomeMatic CCU3 firmware 3.41.11 allows session fixation.

published 2019-10-17 7y ago modified 2026-06-17 4mo ago also EUVD-2019-6765

cvss: 7.3; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.8%; EPSS 0.8% chance of exploitation in 30 days, percentile 57%
public exploits: 0; none known

eQ-3 HomeMatic CCU3 firmware 3.41.11 allows session fixation. An attacker can create session IDs and send them to the victim. After the victim logs in to the session, the attacker can use that session. The attacker could create SSH logins after a valid session and easily compromise the system.

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Exploit prediction

0.82% chance of exploitation in the next 30 days, higher than 57% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

noskill1337.github.io https://noskill1337.github.io/homematic-ccu3-session-fixation referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.1	7.3	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N
NVD	2.0	4.9	AV:N/AC:M/Au:S/C:P/I:P/A:N

Classification

Weakness

CWE-384 Session Fixation

References

noskill1337.github.io /homematic-ccu3-session-fixation
exploit, mitigation, third-party-advisory
eq-3.com /products/homematic.html
vendor-advisory

Sources

CVE List CVE-2019-15849
NVD CVE-2019-15849

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