cbcvebase.
CVE-2016-4521
published 2016-05-31

CVE-2016-4521: Sixnet BT-5xxx and BT-6xxx M2M devices before 3.8.21 and 3.9.x before 3.9.8 have hardcoded credentials, which allows remote attackers to obtain access via…

PriorityP260critical9.8CVSS 3.0
AVNACLPRNUINSUCHIHAH
EPSS
2.46%
82.5th percentile
Sixnet BT-5xxx and BT-6xxx M2M devices before 3.8.21 and 3.9.x before 3.9.8 have hardcoded credentials, which allows remote attackers to obtain access via unspecified vectors.

Affected

4 ranges
VendorProductVersion rangeFixed in
sixnetbt-5_series_cellular_router_firmware<= 3.8.20
sixnetbt-5_series_cellular_router_firmware<= 3.9.7
sixnetbt-6_series_cellular_router_firmware<= 3.8.20
sixnetbt-6_series_cellular_router_firmware<= 3.9.7

Detection & IOCsextracted from sources · hover to see the quote

  • Target devices are Sixnet BT-5xxx and BT-6xxx series M2M cellular routers; detect exploitation attempts by monitoring for successful authentication to these devices using factory/default credentials from unexpected or external source IPs.
  • Public exploits exist for this vulnerability; monitor network traffic to Sixnet BT-series routers for remote authentication attempts, especially from internet-facing sources, as exploitation requires no authentication and low skill.
  • Flag any remote access to Sixnet BT-5xxx/BT-6xxx devices running firmware versions prior to 3.8.21 or prior to 3.9.8, as these are the vulnerable version ranges.
  • ·The specific hard-coded credential values (usernames/passwords) are not publicly disclosed in the advisory; the advisory only confirms their existence as factory accounts. Defenders should consult Sixnet/Red Lion directly for the credential details to use in detection rules.
  • ·The attack vector and protocol used to exploit the hard-coded credentials are unspecified ('via unspecified vectors'), limiting the ability to write precise network-layer detection signatures.

CVSS provenance

nvdv3.09.8CRITICALCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.010.0CRITICALAV:N/AC:L/Au:N/C:C/I:C/A:C
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