vsftpd on TP-Link C2 and C20i devices through firmware 0.9.1 4.2 v0032.0 Build 160706 Rel.37961n has a backdoor admin account with the 1234 password, a backdoor guest account with the guest password, and a backdoor test account with the test password.
The product initializes or sets a resource with a default that is intended to be changed by the administrator, but the default is not secure.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| C2_firmware | Tp-link | * | 0.9.1_4.2_v0032.0_build_160706 (including) |
Developers often choose default values that leave the product as open and easy to use as possible out-of-the-box, under the assumption that the administrator can (or should) change the default value. However, this ease-of-use comes at a cost when the default is insecure and the administrator does not change it.