Describe CVE-2018-19989.
What is CVE-2018-19989?
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..