In the /HNAP1/SetQoSSettings message, the uplink parameter is vulnerable, and the vulnerability affects D-Link DIR-822 Rev.B 202KRb06 and DIR-822 Rev.C 3.10B06 devices. In the SetQoSSettings.php source code, the uplink parameter is saved in the /bwc/entry:1/bandwidth and /bwc/entry:2/bandwidth internal configuration memory without any regex checking. And in the bwc_tc_spq_start, bwc_tc_wfq_start, and bwc_tc_adb_start functions of the bwcsvcs.php source code, the data in /bwc/entry:1/bandwidth and /bwc/entry:2/bandwidth is used with the tc command without any regex checking. A vulnerable /HNAP1/SetQoSSettings XML message could have shell metacharacters in the uplink element such as the `telnetd` string.

D-Link DIR-822 Rev.B 202KRb06, DIR-822 Rev.C 3.10B06, DIR-860L Rev.B 2.03.B03, DIR-868L Rev.B 2.05B02, DIR-880L Rev.A 1.20B01_01_i3se_BETA, and DIR-890L Rev.A 1.21B02_BETA devices mishandle IsAccessPoint in /HNAP1/SetAccessPointMode. In the SetAccessPointMode.php source code, the IsAccessPoint parameter is saved in the ShellPath script file without any regex checking. After the script file is executed, the command injection occurs. A vulnerable /HNAP1/SetAccessPointMode XML message could have shell metacharacters in the IsAccessPoint element such as the `telnetd` string.