Asklemmy

Put a backdoor and keylogger on the network engineer/networking teacher's computer when I was a TA for his class and was able to get full control over the entire district's network from home. I installed GTA2, Diablo 2 and Counter-Strike onto every machine in the system, then would play with my friends (and even a couple teachers) whenever I had the chance.

The security was non-existent, and after just a month it felt like everyone knew about the games but no body ever found out who put them there. :)

As a teacher: I would change the computer hooked up to the projector to Dvorak layout and forget to change it back.

Made a basic script with a nested loop to burn ~20 mins before playing some annoying sounds using the PC speaker. The PC must have been a <=286. I started the script once just before the English teacher arrived and disconnected and hid the keyboard. It resulted in some entertainment when he had to try to silence the PC, but eventually he found the power button.

Notepad could read/write everything so I used it to temporarily disable the dumb software that locked things down to a typing game, a "bible study" game, and Notepad. When they found out I wouldn't admit to anything and they had no idea how I did it. I could literally type faster than the computer could keep up with in the typing game so I could sit back while it caught up to me and still get a perfect score, which really sealed the deal for me that they were wasting my time in "typing class" and it wasn't worthwhile to punish me for whatever it was I did that let me take over any school computer I wanted without apparently changing anything about it that they could figure out.

Used a old password sniffer or something that revealed stored password. Turns out it was the root password for the whole school network LMFAO! Still use the password till this day with added characters 😂😂😂

Put some VB script (I think) that opened and closed the CD-ROM 50 times inside a startup folder. Did it on all computers. Also put a batch file there that shuts down the computer one second after logging in on all teacher computers.

And last but not least, I created a phishing Facebook page, opened it on some browsers in school, rewrote the URL to a Facebook one (without pressing enter) and left it there, collected some passwords.

Edit: Also installed Ubuntu (dual booted) on the computer I usually used.

Edit2: Disabled the tracking software for a computer I used. Damn, it's all coming back to me! Good times.

Installed VNC software on the classroom computer. Simply added a random character when teachers tried to login to various websites, or closed the current page when they weren't looking.

Got caught after a week, for laughing too obviously on the back row.

Nearly got expelled for "hacking", and all staff was recommended to change their passwords for everything.

Our network had a program called "deep freeze" on every computer that was basically an automatic system restore point.

A friend worked for IT during the summer and got the password to turn it off. I could make any change I wanted and make it 'permanent'. I didn't do this much. My favorite hobby was opening word docs that students saved on shared drives and replacing the word "the" with profanity.

I graduated in 2000. During my 11th year, I had an economics class in the same room as a computer lab. Over the course of a few weeks, I downloaded a voice synthesizer program, Shit Talker, to all the computers and set up scripts to have them all begin "talking shit" about our educationally worthless instructor (he taught because he wanted to coach sports), all sequentially during a class a few weeks in the future.

What I didn't think about is how I was one of maybe four or five computer literate students in my grade, so I was quickly targeted after it went off. I should have just denied having done it but I was a dumb teen; they were bluffing about knowing it was me and I fell for it. I had computer access revoked for the rest of my public school career.

Soooo...a bit later that year, my father brings home a very small, defunct computer from his work. It was this custom job consisting of a tiny motherboard, smaller than a micro ATX, with a couple of daughter boards for all its peripheral connections. He just stole it because he thought it was cool but, being pretty computer illiterate, didn't know what to do with it. I gutted it, installed the innards in a plastic file folder box, and installed Windows 98. I now had a portable computer! I'd carry it to my classes, hook it up to a monitor, and use that instead. I initially caught flak for it but I was restricted from using school computers, not their monitors.

In high school, my friends and I were getting into Ubuntu. We were smug Linux nerds. We came up with the idea of installing Linux on one of the school computers. The challenges in doing so was, how to do so without the teacher noticing and getting into the locked bios. The teacher problem was solved when we got a little bit of time when the teacher would step out of the room sometimes. We picked a desktop that wasn't being used by anyone at the time in the class. The other problem was getting into the bios to boot the drive. Long story short, we were able to switch a jumper on the motherboard to clear the bios settings and let us boot the drive. With Ubuntu installed, it took all of about a day for the school to take that PC to the IT gulag. I think they were very confused and threw it out. We didn't want them to just throw more desktops out so we stopped our shenanigans there.

Figured out how to install a ton of games on school laptops. School was pissed that I was running a Minecraft server

I'm old enough that typing 55378008 into my scientific calculator and then turning it upside-down absolutely fits the criteria.

In college we had courses on Linux and we were able to SSH on other students' computers. First I used innocuous commands that ejected the optical drive or that enabled the screensaver.

But unfortunately it escalated quickly and soon every student would mess with each other by shutting down the computers...

Ok, I'm old and this wasn't a computer prank but it's along the same lines.

I used to have a digital watch that functioned as a small universal remote. (It looked like an 80's calculator watch with tiny numbers.)

You did have to program it with the universal code for that brand, but my middle school had bought their TVs in bulk, so the ones permanently mounted in the rooms were all identical models.

I simply programmed my watch to that model, and I'd occasionally keep turning the TV on during a lesson. I did it fairly infrequently, and always in different classes so as not to give myself away.

I never got caught. Back then Tvs only went to channel 100-120ish without special equipment for satellites. If they went higher I would have LOVED to keep changing it to channel 666.

I realised the school PC’s boot order was A:, then C:, booted into DOS from floppy to get behind their own autoexec.bat, installed my own which just repeatedly echo’d “Teachers suck”.

They had some shitty network config utility, which was relying on a weird script language (from a company called BFC Computers). Anyway, it synced some assets down to customise a series of crappy programs with licenses and “Property of Bangsbostrand Skole” messaging. I changed to it randomly (about once a month, across their fleet or 50-ish PCs) retrieve a different set of strings and pictures which all said “Teachers suck”.

I was banned from the computer lab for a year. They fixed the autoexec issue within a day (after calling “very expensive consultants, young man!!”) but when I left some their PCs would still occasionally display “Teachers suck” instead of “property of” in various programs.

My school had a shared drive where anyone could create files and folders. There was one folder where people would put random things (bash scripts downloaded from the internet, pirated minecraft, etc.). I wrote a python program that would display a picture of a pineapple on your screen (no ability to minimise, or move other windows in front of it). I had python installed to one of those folders that only appears if you select "show protected operating system files". I later wrote a remote-control script that communicated by creating files on the network. I was able to control the mouse and keyboards, open applications, take screenshots, and monitor keypresses (I never got anyone to click on it without me telling them to though). Never got discovered for any of it...

Used netsend to send dank memes to every connected PC in the school.

Replaced one teacher's desktop background with a screenshot of the desktop, then hid all the icons and minimized the taskbar.

Got admin access on one of the lab computers to install something needed for a class, and swapped out a bunch of the default Windows sound effects (login etc) with random other sound clips.

Torrented Flatout 2 onto one of the library computers and found out years later a bunch of kids were still playing it during lunch/recess

I didn't, but a classmate shoved a piece of pizza in the CD drive.

10 FOR X = 1 TO 20000
20 FOR Y = 1 TO 20000
30 NEXT Y
40 NEXT X
50 BEEP
60 GOTO 50

IT removed games. I put them back in, but renamed the games, as well as the folder that they were hidden in. Then told people that I was sworn to secrecy BUT, and how to get into the games. I knew that I won when I caught a couple instructors playing it.

I ran a cgiproxy instance with proper ssl certs that totally bypassed and trivialized the school's internet filter. It was password protected with unique passwords per user and I had it set up in such a way I could tell when a password "got out" and I'd cancel it. It got added to the blocklist a couple times, but I was ready because I'd already registered like 20 dynamic dns services to point to the server. It would take them months to add it to the manual blocklist but just a minute to change a link on my forum so people used the next address in line. It was an open secret that I was running it, but I was pretty smart in how I ran it and who I provided access to. I also ran a forum that was popular with the student body and the passwords to the proxy were given out there, but only to people I trusted and could reasonably deduce who they were. Even then they didn't know it was me running the whole thing.

I mean most people probably did, but again I did it in such a way there was never any real paper trail. I never made any money or wanted any clout for it. I just thought it was fun that I got pissed off at the internet filter blocking newgrounds one day and thought "absolutely not", and basically trivialized the filter schoolwide.

Not neccesarily the computers but I used to have a phone with an IR blaster on it and had some fun with the projectors doing that

I found a blue screen of death screensaver online and I installed it on all the school library computers back my my freshman year.

Nice try, FBI guy. We are not divulging any of our past felonies.

Edit: oh boy, was I wrong...

If WinNuke rings a bell. You remember the fun :-)

Open a small program. Type in the IP address. Click Nuke. Target PC immediately shuts down. While it's rebooting you grab it's IP address as your own so it can't rejoin the network. Worked great in a building where every machine had a predictable fixed ip. Some good teenage mayhem.

Booted Macs into single-user mode and set a root password, then logging in with ssh from across the room and killing stuff that other people were running.

Had a class that was just taking old computer parts and building working systems. Installed SubSeven on some classmates’ systems and did shenanigans. Came in handy while we played Starsiege Tribes.

Does writing an infinitely looping stream of 1s and 0s program on my math teachers ti-84 count?

She didnt know how to stop the program so she took the batteries out

I wiped a schools Chromebook to install linux on it. Somehow never got caught even when I had to turn in the computer after graduation.

A teaching seminar was held in one of the classrooms that I took a class in. Students came in the next morning to see a username and password on the whiteboard. It didn't take long for us to test it on school computers.

The account had admin level access and could go into any student's directory. This led to rampant cheating on homework and labs.

I used it on my physics labs in senior year. I, and a few others, were caught and had to make up a few of the labs in the early morning in order to be able to take our finals. Also had detention for weeks.

A year later, after I had graduated and was in college for CS, I applied for a job at the school as a system administrator. The guidance counselor was in the room when I was talking to the IT admin. When I left, she brought up how I had broken policy and accessed files via that breach. The IT admin found me in the hall and asked me about it. I explained that I had taken my punishment, made up the labs, and didn't feel that it would affect my work at the school, but would withdraw my application anyway.

discovered a workaround that i could get to the C drive, then discovered a program that could change the wallpaper and info text on the computer (the change was local to that specific computer). had a little bit of fun with that a couple of times. i also brought in a USB stick with Linux Mint installed on it and booted to that whenever i had free time (i mostly browsed the safe side of the darkweb [back when it was still interesting] and made keygen music in OpenMPT). fun times those were. also booting to mint led me to fully switch to linux so ye :)

ITT: people admitting to violations of 18 USC 1030, which is a terrible law that is way too vague.

I graduated high school in 1996 so internet access at school wasn't really a thing at that point. It was planned to be introduced in the next year.