Weird server requests
So I'm the server admin and web developer for my school's robotics team. I look through the servers access logs every once in a while just to check on things. I keep seeing requests that look like someone's scanning for vulns. But I'm seeing something I've never seen before. It looks like someone is sending requests in machine code and I have no idea why or what it would do???
here's the request:
"\x03\x00\x00\x13\x0E\xE0\x00\x00\x00\x00\x00\x01\x00\x08\x00\x02\x00\x00\x00" 400 166 "-" "-"
7 replies
Probably just testing for some vulnerability. If you're current on patches, you can just disregard as background noice. If it really happens a lot, setting up something like Fail2ban would be useful.
Edit: A quick google search suggests it looks like a Windows Remote Desktop packet header. So something scanning the internet for machines with open RDP
Is the server exposed to the WAN? If so, what ports are forwarded to it? Do you know where these requests are coming from?
Yeah, its running a website. All ports are on default deny except 22, 80, 443, and 9050. 9050 is for the onion version of the site, and 80 auto-redirects to the https version of the site. 22 is rate limited to help protect against brute-force attacks. The requests are coming from multiple IPs, some of them are 117.72.47.192, 172.71.184.89, and 162.158.87.100. the one that sent that specific packet is 82.147.85.33 and no user agent is provided. Most of the malicious packets have user agents attached, but that specific one doesn't I also am seeing another weird one sent by 138.197.16.14
they’re all attack attempts. set up fail2ban, enforce ssh key-based authentication, run it in a non standard port and create firewall allow lists for trusted users, networks or countries if you can. make sure everything is patched frequently.
expect consequences for running onion hidden services - captchas and denied service for that IP address, but also attacks against the hidden service itself.
Probably best to keep the ssh key-based authentication...
ah yeah I meant to type “enable”.
thanks - changed
What port was this sent to, and what webserver are you running (if it was sent to a webserver)?
This reminds me of the string to strigger the really bad apache vulnerabilities that lead to being able to read from the whole filesystem (path traversal), or get a shell on your system (remote code execution). It's likelu that bots are spray and praying attempts across the internet. As long as you're up to date, you should be good.