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z5061241 · 5 years

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Week 2: lecture 2

Notes, thoughts and reflections

Note for tutorials: Listen to others -> "What can i get out of that thats good?"

follow Kevin Mitnick -> art of deception

Read Bruce Schneier (twitter too)

T-shirt design for course

Recon

Recon is the first step in an attack, good attackers will spend a looot of time doing detailed recon of their targets

Type Types:

Active: You do something thats visible to the target, something that leaves a trace

Passive: Doing recon that doesn't leave a trail

Dumpster Diving: Going through the garbage.

Shredding Analysis

Problems with Security

Human Weakness: Humans are flawed, security can exploit these flaws

Complexiity: Double edged sword as it can lead to mistakes and vulnerablities that can be exploited

Asymmetry: Defender has to defend all points, attacker only needs to find one weak point

Weakst Link: Systems are as secure as the weakest part

Hubris: False pride, not being aware of your own weaknesses. Defenders only look at all the strong links

Abuse of trust

Codes

Ways of discretely communicating

-ve: Requires a shared secret which can be quite hard to setup

Classical Ciphers

Secret is small, plug it into a system and that allows further communication

Substitution: Exchanging one letter/symbol/group of letters for another

Attack: Frequency Analysis

Transposition: Rearrange the letters

Attack: Frequency Analysis

Steganography: Hiding a message

Most common letters in English: ETAOIN SHRDLU

Lack of order (entropy) allows us to do manual cryptographic analysis and crack codes

common password: pegasus backwards or swordfish

vignere cipher: each letter is caesar shifted

Kasiski test (identify length of key) and use the index of co-incidence (identify if written in same language)(useful in exams)

Enigma: Understand the weakness in how it was used that allowed it to be cracked

Each letter was substituted by a different substitution cipher (6 rotors)

what did the operators do that was dumb? about 4 things

OTP: One Time Pattern

Every letter in the message is shifted by a random amount. All you actually know is the length of the message, when you try to decrypt there may be multiple solutions, so you never know if you got it right

Issue with OTPs: How do you get the key to the other party?

These are stil used

Tempest attack: analyse electromagnetic radiation from a distance away and reproduce the same screen

Number stations: radio station where a voice just repeats numbers -> Countries used to use them to send info to spies who decode with OTPs

Lava-lamp Random Number Generator

Coincidence Index

Putting two texts side-by-side and counting the number of times that identical letters appear in the same position in both texts.

Application: Determine when two texts are written in the same language using the same alphabet.

Quick Manual Trick: Print out the cipher text and line it up with a copy of itself, shifted a few places or by a whole line say. Then count the number of times the letter in the first copy matches the letter it is aligned with in the second copy. The number of such "coincidences" divided by the length of the message is a not-hopeless(tm) estimate of the coincidence rate of the text. Multiply that number by 26 to get an estimate of the Coincidence Index.

Type 1/Type 2 errors

Quadrant biverate analysis

False Positives / False Negatives:

Predicate win and they don't, Predicate they won't win and they do

You have to choose between -> You can minimise one by minimising the other, you can't minimise both unless you spend "buckets of money"

When you design systems you need to know about handling or trading off both

Anatomy of an Attack

Someone is targeted

They do something dumb, which gives hacker access

The exploit spreads until it is around the whole company

Technical Exploits are not always the center of the attacks, sometimes its more social engineering

Weekness of the week

Self Interest: Humans are always acting in their self interest

Build a system that works in spite of self interest. Communal Balance of individuals Self Interest (Gov vs Opposition)

Exercises to do in the future

Exercise 1: FOI Planning

Freedom of Information Legislation (National + State Level)

Think of information to use in groups

Lodge an FOI request and get information back

what sorts of information would be good to know?

Exercise 2: Data Centers

Work out some data centers are

Where are the international cables landing

Do security analysis of the buildings (How well is this data kept secret?)

#wk2 #lectures

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elenaril · 1 year

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Times Like These “I’m not… I don’t want to die, Johnny. I’m not ready.” She sucked in a sharp breath of air, and blinked away the tears again. “I’ve considered every single fucking option and choice we have, and it’s just. It’s not looking so good, y’know? The malfunctions are getting more frequent, I barely know who and where I am most days after waking up, I’m forgetting things, things that are important, and I just. I don’t fucking know anymore. I’m just not sure if it’s worth it anym-” She was trembling, the thought of an ending sending her into a quiet panic

“Fucking finally, do you ever take breaks like a normal person?” Johnny’s digital form glitched into visibility, grumbling as usual. Eden had finally sat down on a bench, in one of the many hidden nooks and crannies of Kabuki, letting out a quiet groan as she stretched her shoulders, and flexed her hands. The streets were, as every other place in NC, littered with trash and discarded items, and the scent of cheap liquor, smoke from the various industrial sites (or a certain engrams’ phantom cigarettes), garbage - the holy trinity of NC, filled her nose. Even after almost a decade in the dystopian hellscape that was Night City, she couldn’t help but make a face.

“Hey, legendary rockerboy/terrorist/most impressive man you’ll ever meet to planet gonk? You listen to anything I’ve said in the last five minutes?” Eden, aka “planet gonk”, apparently, rolled her eyes. Johnny was pouting, tapping his foot against the ground, arms crossed, looking down at her, huffy and annoyed, and obviously in need of attention. She sighed, and sat up straight, crossing her own arms in response, and looked up at him. “What? If you couldn’t fucking tell, I was trying to relax, something you’ve been bitching about for the last two hours.” They’d just got back from a gig, escorting a client to safety; some idiot who had gotten caught up in corporate schemes, and now had a bounty/potential death sentence on his head. Nothing Eden wasn’t familiar with.

“As I was saying, which you’d fucking know if you ever bothered listening - you’re fucking starving, and your lack of self care is impacting me, so get your ass over to that takeout place over there. I don’t know about you, but even in my glitched out form, I can tell shit smells amazing. Might also just be me.” he finished, adding a wink to top it all off, along with a smug grin. Fuck, she thought to herself. He was absolutely right. She had not eaten a single thing since the previous night, and that had been a half-eaten, cold Burrito XL she’d gotten herself for breakfast.

“Okay, fine, you have a fucking point. About the food, thank you.” With a grunt, she got to her feet as Johnny’s construct faded away, and shuffled through the street, zigzagging between the other NC residents, and trying to avoid stepping in something nasty.

As she neared the little eatery, the scent of grilled meats and whatever vegetable substitute they were using, filled her nose, and she felt a pang of hunger. Fucking Johnny and his terrible (good) ideas. Even though the place was open, facing the streets, it was surprisingly cozy. It served as a quiet little pocket, where one could find some peace and quiet, at least this time of night. She stepped towards the counter, pulling her jacket slightly tighter around herself. She smiled at the chef, and leaned across the bartop, placing her gun within reach on the counter, just in case. Night City etiquette and all that. She placed an order for a simple stir-fry, and within minutes, a takeaway container was placed in front of her. She closed her eyes for a brief moment, trying to shrug off the nausea that plagued her, due to the various medications Vik and Misty had given her, to deal with the Relic. She picked up the chopsticks, and began eating. A wave of satisfaction washed over her, and she knew that it was not all her own. The chef was busy tending to a pair of customers at the opposite side of the counter, and the rest of the little eatery was empty. It was nice, being able to sit down and just enjoy the peace and quiet for once, and get lost in her own thoughts.

“Don’t get too comfortable, princess. With all those loud ass fucking thoughts you’re having, I might get the impression you don’t like me.” Eden rolled her eyes and stuck the chopsticks in the container, pushing it aside.

“Can I seriously not have anything nice without you ruining it?” She huffed and leaned over the counter again, flexing her hand.

“Hey, I practically bought you dinner, I can be nice. Not my fault you’re being such a bitch about it.” Eden swatted at him with her left hand, both feeling the impact for a short second, before her hand glitched through his arm, leaving a jitter of code and static, before settling back into him. He snickered, and shook his head, before pulling out a cigarette. Eden refused to humour him further, and instead chose to look away.

They stood there in silence, side by side. Johnny smoking, Eden lost in thought, much like usual. The food beside her was getting cold, and a sharp pain at the nape of her neck that spread down her spine, straight to her chest snapped her back into reality. Johnny winced, feeling it too, and he turned to look at her, as she sucked in a sharp breath of fresh air.

“‘m fine, don’t worry.” she muttered, flexing and clenching her fist repeatedly, trying to ground herself. Johnny’s eyebrows furrowed in concern, and he took another drag of the cigarette, waiting for her to talk. But she didn’t say anything. Instead, she kept standing here, hunched over the counter, flexing and clenching her fist, focusing on the repetitive movement, and ignoring the tension in the rest of her body. The nausea was back, and she felt cold.

“...you alright, V?” Johnny reached towards her, and put a hand on her arm. She flinched, but leaned into him. Barely. She took another deep breath, and exhaled shakily.

“I’m… I don’t know. It’s getting worse.”

“...”

Johnny looked at her, and he could feel her growing desperation, the two of them connected in both body, and mind. He felt her agitation, and it had been getting harder and harder to shut each other out. The Relic was working as intended, blurring the lines between them, and erasing her in the process. They both knew that it was only a matter of weeks at this point.

Eden yanked away her arm, and leaned down, burying her head in her arms. She felt the familiar sting of tears in her eyes, and aggressively attempted to blink them away. Johnny, not taking a hint, or ignoring it, as usual, reached over, and gently stroked the back of her neck with his organic hand, brushing the rose-coloured hair away. He did not push his luck, however, and removed his hand shortly after. Eden was holding her breath.

“...you wanna, I don’t know. Talk about it?” Johnny was toeing in foreign territory for them both. They had free access to each other’s feelings, and Johnny could read every single thought that crossed through her head, but talking about things? They were both terrible at it. But, they tried, when it mattered. And tonight, it mattered.

Eden stood up again, brushing her hands through her pink bangs as she straightened slightly, before resting her arms at the counter, fists clenched. She refused to look at him. If she did, she would probably break down. And that, she refused.

“Johnny, I…” Johnny lit another ghostly cigarette, and looked at her, his usually sharpened gaze, soft.

“I’m not… I don’t want to die, Johnny. I’m not ready.” She sucked in a sharp breath of air, and blinked away the tears again.

“I’ve considered every single fucking option and choice we have, and it’s just. It’s not looking so good, y’know? The malfunctions are getting more frequent, I barely know who and where I am most days after waking up, I’m forgetting things, things that are important, and I just. I don’t fucking know anymore. I’m just not sure if it’s worth it anym-” She was trembling, the thought of an ending sending her into a quiet panic.

“Lighten up, princess.” Johnny looked away, and stared right in front of him. It was like any other of his usual, snarky comments, but there was nothing of the sort in his tone. He took a deep drag of his cigarette, and exhaled it, the smoke glitching into nothing. There was an air of solemn stoicism in his words, as he continued.

“We’ll get you and that thick fucking skull of yours out of this, just trust me. If there’s anyone who’s stupid enough to come up with an insane, last minute plan, and lucky enough to go through with it, and come out on the other side? It’s you.” Eden stood there, quietly, as Johnny turned to look at her, again.

“You’re an absolute fucking nightmare, Eden, but we’re in this together. You took a bullet for me, and I’ll take the Blackwall for you.” Eden shuddered at the thought, and looked down again. When she spoke, it was barely a whisper.

“...I just. It’s stupid. But I just hoped there’d be a way we’d both make it out of this fucking mess. It’s just not fair. We both deserve better.” Johnny smiled, and let out a chuckle, and Eden looked up at him, teary-eyed and confused. “You almost had me there, princess. I almost thought you cared about me, for a second.” She let out a snort, and rolled her eyes, elbowing him in his side, as he flipped her off and blew a cloud of smoke in her face in return. She shook her head, and grabbed her gun, before leaving a few eddies for her meal. They had to find a solution. They still had time. For now. She tightened her jacket around her, the Samurai emblem at the back glowing a deep red, and they walked back into the alley, and into Night City. Eden leading the way, fast-paced and determined, and Johnny, nonchalantly strutting along, glitching in and out of view as he pleased. They still had time.

#cyberpunk 2077 #cp77 #cdpr #virtual photography #oc: eden valentine #otp: edge of entropy #johnny silverhand #skelly's stuff #lore #writing

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