Multiple recent articles allege firmware allows backdoor access to some D-Link and according to some some older articles some TPLink routers as well.
Includes wired and wireless models.
Research using your own internet searches. Suggested keywords:
[D-Link backdoor] [tp-link backdoor]
D-Link to padlock router backdoor by Halloween
D-Link will address by the end of October a security issue in some of its routers that could allow attackers to change the device settings without requiring a username and password.
The issue consists of a backdoor-type function built into the firmware of some D-Link routers that can be used to bypass the normal authentication procedure on their Web-based user interfaces.
The fix, when available, will require users perform a firmware update. (assumes all affected routers are still supported or firmware will be provided for all affected models)
Alternate fix if router supports it, is to flash firmware with vetted Open-Source Open/DD-WRT instead of manufacturer's firmware (which may void warranty, etc).
Note: Flashing firmware always includes a degree of potential for turning hardware into a brick/paperweight.