### [CVE-2021-28839](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-28839) ![](https://img.shields.io/static/v1?label=Product&message=n%2Fa&color=blue) ![](https://img.shields.io/static/v1?label=Version&message=n%2Fa%20&color=brightgreen) ![](https://img.shields.io/static/v1?label=Vulnerability&message=n%2Fa&color=brightgreen) ### Description Null Pointer Dereference vulnerability exists in D-Link DAP-2310 2.07.RC031, DAP-2330 1.07.RC028, DAP-2360 2.07.RC043, DAP-2553 3.06.RC027, DAP-2660 1.13.RC074, DAP-2690 3.16.RC100, DAP-2695 1.17.RC063, DAP-3320 1.01.RC014 and DAP-3662 1.01.RC022 in the upload_certificate function of sbin/httpd binary. When the binary handle the specific HTTP GET request, the strrchr in the upload_certificate function would take NULL as first argument, and incur the NULL pointer dereference vulnerability. ### POC #### Reference - https://www.dlink.com/en/security-bulletin/ #### Github No PoCs found on GitHub currently.