The D-Link NPAPI extension, as used on D-Link DIR-850L REV. A (with firmware through FW114WWb07_h2ab_beta1) and REV. B (with firmware through FW208WWb02) devices, does not verify X.509 certificates from SSL servers, which allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.
D-Link DIR-850L REV. B (with firmware through FW208WWb02) devices have a hardcoded password of wrgac25_dlink.2013gui_dir850l for the Alphanetworks account upon device reset, which allows remote attackers to obtain root access via a TELNET session.
D-Link DIR-850L REV. A (with firmware through FW114WWb07_h2ab_beta1) and REV. B (with firmware through FW208WWb02) devices use the same hardcoded /etc/stunnel.key private key across different customers' installations, which allows remote attackers to defeat the HTTPS cryptographic protection mechanisms by leveraging knowledge of this key from another installation.
htdocs/parentalcontrols/bind.php on D-Link DIR-850L REV. A (with firmware through FW114WWb07_h2ab_beta1) devices does not prevent unauthenticated nonce-guessing attacks, which makes it easier for remote attackers to change the DNS configuration via a series of requests.
D-Link DIR-850L REV. A (with firmware through FW114WWb07_h2ab_beta1) and REV. B (with firmware through FW208WWb02) devices have 0666 /var/passwd permissions.
D-Link DIR-850L REV. A (with firmware through FW114WWb07_h2ab_beta1) and REV. B (with firmware through FW208WWb02) devices have 0666 /var/etc/hnapasswd permissions.
D-Link DIR-850L REV. A (with firmware through FW114WWb07_h2ab_beta1) and REV. B (with firmware through FW208WWb02) devices have 0644 /var/etc/shadow (aka the /etc/shadow symlink target) permissions.
D-Link DIR-850L REV. A (with firmware through FW114WWb07_h2ab_beta1) and REV. B (with firmware through FW208WWb02) devices have 0666 /var/run/storage_account_root permissions.
D-Link DIR-850L REV. A (with firmware through FW114WWb07_h2ab_beta1) and REV. B (with firmware through FW208WWb02) devices have 0666 /var/run/hostapd* permissions.
The DHCP client on D-Link DIR-850L REV. A (with firmware through FW114WWb07_h2ab_beta1) and REV. B (with firmware through FW208WWb02) devices allows unauthenticated remote code execution as root because /etc/services/INET/inet_ipv4.php mishandles shell metacharacters, affecting generated files such as WAN-1-udhcpc.sh.