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CVE-2018-18754: Zyxel Vmg3312 B10b Firmware: Hard-coded credentials or backdoor
CVE-2018-18754 is rated critical with a CVSS v3.0 base score of 9.8 and NVD lists Zyxel Vmg3312 B10b Firmware as the affected product. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.
Vulnerability description
ZyXEL VMG3312-B10B 1.00(AAPP.7) devices have a backdoor root account with the tTn3+Z@!Sr0O+ password hash in the etc/default.cfg file.
Severity breakdown
CVSS v3.0 9.8: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
- Attack complexity: Low. No special conditions; the attack can be repeated reliably.
- Privileges required: None. No account or prior access is needed.
- User interaction: None. No action from any user is needed.
- Scope: Unchanged. Impact stays within the vulnerable component.
- Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
- Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
- Availability impact: High. Total loss of availability; the component can be shut down.
Underlying weakness
CWE-522: Insufficiently Protected Credentials
The product transmits or stores authentication credentials, but it uses an insecure method that is susceptible to unauthorized interception and/or retrieval.
Affected products
- Zyxel Vmg3312 B10b Firmware: 1.00\(aapp.7\)