High severity · published Jun 24, 2025
CVE-2025-3091
MB connect line: Authorization bypass in mbCONNECT24/mymbCONNECT24
7.5
CVSS
0.4%
EPSS
No
On KEV
Description
An low privileged remote attacker in possession of the second factor for another user can login as that user without knowledge of the other user`s password.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 32% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MB
mbCONNECT24 · MB connect line
before 2.16.5 · source: vendor
MY
myREX24 · Helmholz
before 2.18.0; before 2.16.5 · source: vendor
MY
myREX24.virtual · Helmholz
before 2.18.0; before 2.16.5 · source: vendor
MY
mymbCONNECT24 · MB connect line
before 2.18.0; before 2.18.0; before 2.16.5 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-3091
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-3091
certvde.com
https://certvde.com/en/advisories/VDE-2025-035
certvde.com
https://certvde.com/en/advisories/VDE-2025-038
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An issue in MB connect line mymbCONNECT24, mbCONNECT24 and Helmholz myREX24 and myREX24.virtual in all versions through v2.11.2 allows a logged in user to see devices in the…