I met my whole family through Baidu Tieba.

Shen Kang couldn't hold back any longer.

Hearing all this, Ma Liang remained calm, but looked at He Qiuzhu and asked, "And then? What did you do after you got the low-privilege account?"

He seemed completely oblivious to the strangeness of "getting authority by treating someone to a meal," instead taking it all for granted.

He Qiuzhu continued her conversation with Ma Liang: "That machine is running LNU kernel 2.6.24. I found a local privilege escalation vulnerability in the cv library, compiled plt, and got t directly."

Which voice actor?

"cv-2008-0600".

"After gaining authority, what did you do?"

"I configured that machine as my jump server, using an H tunnel to encrypt and forward traffic. This way, when I operate here, the source IP address that the network center sees is the internal network address, which will not trigger access control."

"Then you used this jump server to scan the authentication server's port?"

"Hmm. I found a log synchronization module that was running under a default service account, and the password hadn't been changed. I gained access to the logs at the application level through that account."...

Seeing the two of them seriously discussing technical issues he couldn't understand, Shen Kang couldn't help but speak up and interrupt them.

"Stop, stop, I said stop."

Shen Kang stretched out a large hand, blocking the two of them, finally bringing their conversation to a temporary halt.

Then Shen Kang said what he wanted to say.

"Old Ma, you made it sound so complicated, but she accomplished what you struggled to do with just one meal. Don't you think that's outrageous?"

Ma Liang was baffled. "What's so outrageous about this? Isn't this perfectly normal? It just shows that He's hacking skills are superb."

As he spoke, Ma Liang glanced at He Qiuzhu again, thinking to himself, "This face truly embodies the most impressive hacking skills in the world."

Unfortunately, my hardware skills are lacking, so I can't learn this technology.

"Normal? Is it due to exceptional hacking skills?"

Shen Kang was speechless. "You computer science students, is your understanding of 'highly skilled hackers' a little different from ours?"

Ma Liang sat in the chair, looked at Shen Kang, and asked with some interest, "Boss, what kind of person is a hacker in your mind?"

After a moment's thought, Shen Kang slowly began to speak, recounting everything he knew about hackers.

"My ideal hacker attack and defense scenario is one where keyboards fly by, code scrolls across the screen, firewall alerts go off incessantly, and the two sides engage in a fierce battle of wits in the digital world. And you're telling me it's just over a meal, a casual chat, and you somehow manage to get the server's IP address and login password?"

Ma Liang smiled.

"Boss, that's a classic case of prejudice. Actually, the way He got access to P and privileges by treating that senior to dinner is the most advanced hacking technique."

He Qiuzhu, afraid that Shen Kang would misunderstand, whispered a correction: "It was my senior who treated me to dinner."

"..."

Ma Liang's expression froze. "Your senior treated you to dinner? And then she told you the password and the 'p' key?"

He didn't hear clearly just now and thought that He Qiuzhu was inviting the other party to dinner—which would have made more sense—but it turned out that the other party was inviting He Qiuzhu to dinner.

Good grief, so you're going to eat and take things, huh?

He Qiuzhu nodded obediently, "Mm."

Ma Liang was amazed: This person's hacking skills had reached a level he could not even imagine.

Shen Kang, watching from the side, interjected, asking, "Is your computer science department a little different from what I imagined? You really think 'inviting someone to dinner' is a hacking technique?"

He could tell that the two of them seemed to be serious and weren't joking with him.

Upon hearing this, Ma Liang turned his gaze away from the promising junior and looked at Shen Kang.

Instead of answering immediately, he asked in return, "Boss, have you heard of social engineering?"

Shen Kang shook his head and answered truthfully, "No."

Ma Liang said, "This is actually part of social engineering. Eating, making phone calls, pretending to renovate a computer, impersonating a leader to send emails—these are all examples of social engineering."

"..."

Shen Kang was a little nervous. He suddenly felt that putting He Qiuzhu in the computer science department might lead her astray. Listen to what kind of things these people in the computer science department are learning.

The fake computer renovation, the emails impersonating leaders, and the phone call—which is very likely a scam call—are they even a computer science department?

Seeing the speechless expression on Shen Kang's face, Ma Liang got a little excited.

He usually sees his boss with an air of confidence and self-assurance, an expression that is quite rare on the boss's face.

So Ma Liang became more talkative and struck up a conversation with Shen Kang: "Boss, in your opinion, what's the most advanced technique for dealing with a hacker?"

Shen Kang rolled his eyes at him. "I know this: unplug the network cable."

Ma Liang was a little disappointed to see that Shen Kang actually knew the correct answer.

However, he still had his reasons.

"Indeed, unplugging the network cable physically isolates the attacker, so even the most skilled hacker can only attack the air, which can prevent most hacking techniques. However, there is still a side-channel attack that can be carried out without a network cable."

"Side-channel attack?" Shen Kang wondered.

He had never heard of this thing before.

Ma Liang nodded. "Side-channel attack. Simply put, it's attacking electronic devices by exploiting certain characteristics. For example, monitoring electromagnetic radiation."

"Any electronic device radiates electromagnetic waves when it's working. The different content displayed on the screen and the different instructions processed by the CPU all result in different current frequencies and intensities in the surrounding circuits. Even if you unplug the network cable, someone can still listen to these signals by pointing a device at the location where your computer is being used. They can then analyze and deduce your key or the document you are currently reading."

"Besides monitoring electromagnetic radiation, side-channel attacks also involve monitoring CPU power consumption and time delays..."

Shen Kang listened intently.

After listening, he finally spoke up: "It sounds a bit fantastical, very cool."

Ma Liang nodded, then shook his head: "It sounds cool, but it's still in the very early stages, it's still theoretical. The most important method right now is social engineering."

"To the untrained eye, this might sound like a joke, but it really works."

Ma Liang started counting on his fingers.

"For example, if you're worried about your server being hacked, just hide it."

"No port opening, no external services, just a whitelist on the firewall, allowing only specified ports to access. It's so simple even a primary school student could do it, but it works. That's one point."

"Secondly, the passwords aren't strong enough? Force all users to set complex passwords of at least 20 characters, including uppercase and lowercase letters, numbers, and symbols, and change them every three months. Does this solution involve any technical skill? No. But it can block the vast majority of brute-force attacks."

"Then, the most practical consequence of this approach is that everyone will write their passwords on sticky notes and stick them next to their monitors. In the end, the real security vulnerability becomes that sticky note instead of the password itself."

"Thirdly, boss, do you think social engineering is outrageous? Calling customer service and saying 'I'm Teacher Wang, I forgot my password' has a specific name in the information security circle: 'pretext attack'."

Upon hearing this, Shen Kang couldn't help but mutter, "Attack? And it's pre-text?"

"Old Ma, I've noticed that you computer science students are quite good at coming up with names. Fraud is called social engineering, and making fraudulent phone calls is called pretext attack."

Ma Liang laughed and continued.

"Sounds very professional, right? Actually, you're right, boss. To put it bluntly, it's just a scam, the same principle as scammers calling old ladies to trick them into transferring money. There is some technical skill involved, but it's not in the code, it's in the sales pitch."

Fourthly, there is also a UB attack.

"The fastest way to gain access isn't through the network, but by throwing a few USB drives labeled 'Salary Adjustment Plan.l' into the target's parking lot. Someone will always pick them up and plug them into the company computer. This is called 'USB phishing,' and its success rate is ridiculously high."

Shen Kang couldn't help but want to complain again.

Write a "salary adjustment plan" on a Trojan USB drive and throw it in the other company's parking lot?

It's amazing that computer science students came up with this!

"Fifth, if you really want absolute security, then you might as well not connect to the Internet at all. Like that machine in our school that stores the port mapping table, it's not connected to the Internet at all, it's physically isolated."

"You want to hack it? Then first try to break into the network center office, or even climb through the window..."

Shen Kang listened for a long time and was amazed.

Yeah, yeah, those programmers have thin hair, look at what they're researching all day long?

Deceiving people, unplugging the internet cable, hiding things, scavenging trash, breaking into doors, climbing through windows...

However, these methods did serve as a reminder to Shen Kang.

Don't underestimate its effectiveness; it really works.

If Li Xiangjun were to find a USB drive labeled "Anjia Salary Adjustment Plan" one day, knowing her as Shen Kang does, she would definitely plug it into the computer.

I still need to talk to Li Su about this later. Although some of Anjia's important data is currently physically isolated and inaccessible to ordinary employees, we can never overemphasize the importance of network security.

After thinking for a while, Shen Kang saw that Ma Liang had finally finished speaking, so Shen Kang summarized, "So, your line of work, in essence, is..."

"Inviting someone to dinner, lying, unplugging the internet cable, hiding things, scavenging trash, climbing through windows."

Ma Liang continued Shen Kang's words.

After he finished speaking, he laughed at himself.

Shen Kang and He Qiuzhu laughed too, and the air was filled with a joyful atmosphere.

After laughing, everyone remembered their business.

Shen Kang was the main person concerned about this important matter.

He pointed to He Qiuzhu's computer, which had already taken control of the network center's test server. "So now, we can find that 'Happy Pluto'?"

Ma Liang immediately understood and reassured his boss.

"It's not that simple, boss."

"At this point, He Tongxue has only become part of the network center. Next, she needs to obtain access to the authentication and billing system in order to gain the ability to query logs."

Hearing Ma Liang's words and receiving his look, Shen Kang nodded in satisfaction and asked, "This thing must be very troublesome and time-consuming, right?"

Ma Liang nodded, reassuring his boss, "Indeed."

Shen Kang was even more satisfied.

He Qiuzhu suddenly raised her hand, as if to take credit, and said, "No trouble at all! My senior said during lunch that she overheard the teachers at the network center discussing a module of the authentication and billing system that kept giving errors, and that they wanted to upgrade it. She also gave me the approximate service port number."

"...You remembered that?"

"Got it! And I've done it!"

He Qiuzhu stared at Shen Kang, her eyes sparkling, with a hint of wanting to take credit.

Shen Kang remained silent.

Ma Liang glanced at the two men, coughed lightly, and asked, "Student He, how did you do that?"

He Qiuzhu told the truth honestly.

"I first scanned the specific port of the authentication and billing master server through the jump server and found that the service was indeed running. Then I confirmed the module name and version number from the returned bann information."

"Then I searched online for security vulnerabilities in this module and found a problem with the 'default service account'. This account is used for inter-module communication, the password is hardcoded in the documentation and has never been changed, and the permissions are sufficient to query all logs, but cannot modify system configurations, so I wrote a script to mimic a synchronization request and successfully log in using the default account."

"At this point, although I haven't been able to log into the main management interface yet, I've already gained AP-level log query capabilities."

Shen Kang, who had been listening in silence, suddenly spoke up and asked a question.

"What's that senior's name?"

He Qiuzhu, without any guile, blurted out, "Cheng Kexin."

Shen Kang nodded silently.

He Qiuzhu was somewhat flustered and asked, "Shen Kang, what are you doing?"

Shen Kang casually replied, "It's nothing. She's helped you so much. If I run into her again, I'll thank her."

In her heart, she thought that if she ever met this senior, Cheng Kexin, she would definitely give her a big gift to properly "thank" her.

After thinking all this through, Shen Kang cast a pleading look at Ma Liang, "Old Ma, it can even check logs now, and it's only AP level!"

Shen Kang said this through gritted teeth.

Although I don't know what this AP level means, it doesn't sound like it.

Finally, Shen Kang asked, "Does this mean we can find out who that person is?"

Ma Liang did not disappoint him.

Ma Liang shook his head and said, "No, boss. We can only get a number from the logs, but we can't tell from the number which physical world interface corresponds to it. We need a mapping table."

"For example, boss, the network port number in your dorm is bvu. What can you tell from this number?"

Shen Kang shook his head. "I can't tell."

Ma Liang nodded. "Yes. This is actually a password system, a mapping table, that's the password book. Which number corresponds to which dormitory's network interface is all recorded in that mapping table."

"Only by using the mapping table can the number be accurately translated and the corresponding physical world network interface be found."

"And this mapping table, as far as I know, is a CL table, which is stored on a computer in the network center that is not connected to the internet."

Shen Kang felt better.

A computer that's not connected to the internet? Isn't that the ultimate weapon they were just discussing—unplugging the network cable?

Okay, okay, I don't care about all your fancy stuff, I'll just unleash a killer move and leave you completely dumbfounded.

The ultimate weapon still works.

Even if He Qiuzhu is a genius and that senior is a big mouth, can they still break through this move?

"What a pity!"

Shen Kang felt relieved, but his face showed great distress. He made a fist with his left hand and a fist with his right, pounding his left palm hard, sighing and lamenting, just like a theatrical performer on stage, completely affected.

"Since we've encountered the ultimate killing move, there's really nothing we can do!"

"..."

Ma Liang thought to himself, "Boss, could your acting be any more exaggerated? Nobody uses this old-fashioned style of acting anymore, right?"

Shen Kang had no idea what Ma Liang was thinking.

After he finished speaking, he simply turned around, looked at He Qiuzhu, and reached out to pat her head. "Chief Technology Director! You've done a great job today, but human strength has its limits. Since we've encountered the ultimate solution, there's really nothing we can do."

"Don't be discouraged. It's not that you lack ability, but rather that these are the realities. The fact that you've achieved this much is already remarkable! Applause!"

As he spoke, Shen Kang started clapping his hands vigorously.

Ma Liang quickly clapped as well, not so much to cooperate, but because he genuinely felt that He Tongxue was truly outstanding, and with such a face, his future achievements would definitely surpass his own.

He Qiuzhu's eyes were bright and she looked quite happy. There was no sign of discouragement on her face, as if she had been comforted by Shen Kang.

This put Shen Kang at ease.

But then, my heart tightened and everything went black.

"Shen Kang, it doesn't matter if there's no matching table, I can still find that person."

"..."

Just like Ma Liang in the morning, Shen Kang turned into a robot, slowly turning his neck to look at Ma Liang. Just by looking at him, you could almost hear the cracking sound of his neck lacking oil.

"Old Ma, this is allowed? Didn't you fucking say it absolutely had to be a mapping table?"

Ma Liang thought to himself, "When did I say I 'definitely' needed a correspondence table?"

However, he didn't offer any explanation, nor did he say that there was a method that didn't require a mapping table.

Ma Liang simply looked at He Qiuzhu and asked, "Without a correspondence table? What kind of method is that?"

He Qiuzhu then explained in detail to reassure Shen Kang.

"I can now query logs in batches via AP, so I can perform cross-comparisons."

"I can iterate through all the online platforms that I can find in batches, and use an application to perform a log query on each platform, recording the returned account and port name. In this way, I can obtain a 'account-port' mapping table with thousands of records."

"Then, I went to the school's official website and used these accounts to look up their student IDs and names. Then, using the school's online course system or address book system, I found out the corresponding classes and dormitory building numbers of these students."

"By this point, I had two forms in my hand: one was 'Account Number - Port', and the other was 'Account Number - Name - Dormitory Building'."

"By using the common field of 'Account,' the two tables can be instantly linked together to create a final correspondence table of 'ports' and 'dormitories' for the entire school."