CVE-2017-3209

The DBPOWER U818A WIFI quadcopter drone provides FTP access over its own local access point, and allows full file permissions to the anonymous user. The DBPower U818A WIFI quadcopter drone runs an FTP server that by default allows anonymous access without a password, and provides full filesystem read/write permissions to the anonymous user. A remote user within range of the open access point on the drone may utilize the anonymous user of the FTP server to read arbitrary files, such as images and video recorded by the device, or to replace system files such as /etc/shadow to gain further access to the device. Furthermore, the DBPOWER U818A WIFI quadcopter drone uses BusyBox 1.20.2, which was released in 2012, and may be vulnerable to other known BusyBox vulnerabilities.

Weakness

During installation, installed file permissions are set to allow anyone to modify those files.

Affected Software

Potential Mitigations

• Compartmentalize the system to have “safe” areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area.
• Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/1.html
• https://cwe.mitre.org/data/definitions/127.html
• https://cwe.mitre.org/data/definitions/81.html

References

• https://dl.acm.org/citation.cfm?id=3139943
• https://www.kb.cert.org/vuls/id/334207
• https://www.securityfocus.com/bid/97564