D-Link DIR-859 routers contain a path traversal vulnerability in the file /hedwig.cgi of the component HTTP POST Request Handler. Manipulation of the argument service with the input ../../../../htdocs/webinc/getcfg/DHCPS6.BRIDGE-1.xml allows for the leakage of session data potentially enabling privilege escalation and unauthorized control of the device. This vulnerability affects legacy D-Link products. All associated hardware revisions have reached their end-of-life (EOL) or end-of-service (EOS) life cycle and should be retired and replaced per vendor instructions.