For the past 15-20 years, I've been running a little website called Programming Basics that teaches programming to kids. It's an ancient, very amateur website that clearly shows its 20 year age too. It has amateur programmer art. It has JavaScript popovers and other archaic HTML stuff. It has PDFs of handouts that teachers can print out. It's main distinguishing characteristic is that it still works after nearly 20 years, and I haven't taken it down for some reason. It's very obscure, and it receives a very small amount of traffic.
And I think someone tried to DDOS it, but I'm not sure.
I host that website on Amazon Web Services (AWS), and when I looked at the bill a few weeks ago, I noticed that the charges seemed elevated. The per month charges have been pretty much the same for a decade, so I thought I must have accidentally left a cloud computer running or something. But after digging through my billing reports, the charges seemed to be caused by unusual web traffic to my Programming Basics website.
Digging into the general usage statistics provided by AWS, it seems I received 126,755,687 requests for the page "/" on February 28. The day before, I only received 209 requests for that page. The "/" page automatically redirects to the "/en/" page. So typically, I should receive a similar number of requests to the "/en/" page as to the "/" page or even a little more since bookmarks and search engines will usually go directly to the "/en/" page. Instead, I received 785,650 requests for the "/en/" page. That's incredibly high, but it's strange that while most of the clients didn't bother following the redirect, some did. The ones that didn't follow the redirect were obviously basic traffic generating bots that simply generate requests, but why were some bots coded up differently to follow redirects? Accesses to other webpages on the website and accesses on other days seemed fairly reasonable. I wonder why that attack was only for the root page of the website, especially considering that the page was essentially blank? Wouldn't it have been better to access a page with a larger file size? Or a spread of different pages or even non-existent pages? I suppose it doesn't matter since the whole website is a static website anyway.
Digging into hourly usage statistics, it seems that almost all the requests happened in a one hour period:
28.05 GB was used right at 12:00 UTC time. The timing is a little odd. I suppose the attack was scheduled in advance to occur right at 12. But why was it so short? Did AWS recognize an attack was occurring and block it? Or did the attackers only purchase a small DDOS attack, so it couldn't be sustained? Or did the attackers realize that they attacked the wrong target or that it was pointless trying to attack a website hosted by Amazon and call it off?
I'm too lazy to download the gigabytes of logs and do a proper analysis, but when I took a look at one or two log files, it seems like the attack happened around 12:50 UTC and lasted only 3-4 minutes, so maybe it could have been manually triggered after all. But if it was manually triggered, maybe the attacker would manually visit the website to verify if the attack was working or not. If so, I could search through the logs, and maybe I could pick out the request that comes directly from the attacker's computer. Of course, maybe the botnet automatically monitors its own effectiveness. That might explain why some of the requests followed the redirect while others did not. The requests that followed the redirect were actually trying to verify the effectiveness of the attack by sending a normal request to the website and measure its response time.
AWS provides summary statistics of the country where requests came from. The accesses seem to be spread pretty widely geographically, so it really was a distributed botnet. Here's a breakdown of the top few countries where the accesses came from:
- United States 27,235,432
- Bulgaria 15,866,047
- Turkey 6,927,133
- France 6,166,693
- Germany 6,141,788
- Indonesia 6,115,375
- Netherlands 5,347,080
- Canada 5,156,815
- Australia 4,458,130
- China 3,511,069
- India 3,093,340
- Japan 3,039,478
- Vietnam 2,406,960
- Brazil 2,321,232
- Russian Federation 1,859,764
- Iran, Islamic Republic of 1,631,397
- Colombia 1,510,684
- United Kingdom 1,485,535
- Korea, Republic of 1,323,381
- Bangladesh 1,219,066
- Spain 1,170,194
- Thailand 1,081,853
- Finland 1,052,344
- Ecuador 921,248
- Poland 867,562
- Argentina 843,783
- Ukraine 842,882
- Mexico 838,305
- Hungary 719,549
- South Africa 669,794
- Philippines 610,215
- Kazakhstan 599,328
- Italy 540,665
- Luxembourg 532,379
- Chile 512,108
- Libya 486,914
- Venezuela, Bolivarian Republic of 471,266
- Singapore 455,583
- Ireland 435,134
- Peru 396,041
- Latvia 357,309
- Dominican Republic 353,845
- Sri Lanka 314,126
- Norway 298,881
- Albania 268,222
- Myanmar 235,063
- ...
I just looked at a few log entries of requests, it seems like some clients only made a few requests while other clients would submit hundreds of requests, all within the span of a few seconds. Just randomly grabbing a few IPs from the logs and doing IP lookups, it looks like the requests seemed to be coming from compromised servers in various data centers. Just grabbing some random IPs, I can see Hurricane Electric, Heymman Servers, BelCloud, RK Telecom, Maxnet Telecom, Min Proxy Company--just a lot of servers from all over. I wonder if these are compromised servers or cloud servers bought using stolen credit cards. Is it possible to report these servers to the service providers as being compromised so that they can be taken down and fixed?
So overall, it does seem like I was the victim of a DDOS, but since everything is cloud-hosted, I didn't really notice at all. To be honest, the site is so off my radar, I don't think I would have noticed even if the DDOS really had taken down the website and made it inaccessible. Honestly, I can't fathom why someone would want to run a distributed denial of service against the website. It's a really insignificant site with little traffic and no commercial value, so there can't be any commercial reason to try to knock it off the Internet. I don't think any Internet scammers sent me any threats or extortion messages asking for money to avoid a DDOS. I even looked into my spam folders and didn't see anything there. Maybe I pissed someone off on the Internet and they decided to attack back by hiring a DDOS service, but I don't think I annoyed anyone on February 28th. Perhaps I annoyed someone before then, and they only scheduled the attack for later, but that seems to defeat the point of a DDOS if it just seems random and doesn't cause me to fear that hackers are out to get me.
So a DDOS attack was made against my website. But it was over in three minutes. I don't know why it ended so quickly. I didn't even know about it until a week later. I don't know why I was attacked. It's all just very confusing and mysterious.
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