Chapter 122 Screening: Discarded Training Terminals

Jiang Ling didn't urge Liang Jiushan any further. Instead, she waited quietly for him to shut down the computer and put it back in his backpack before leaving the office with him and heading to the technical team.

Li Bin from the technical team was already overwhelmed with work, but when he saw Liang Jiushan come over, he was overjoyed and dragged him to sit down in front of the computer: "Come on, you can operate it."

All the technicians rushed over and stood behind Liang Jiushan, eager to learn how to find traces of the other party's crimes online.

When discussing his profession, Liang Jiushan is confident and determined, radiating an aura of light.

"Didn't he steal the keys to open doors and steal things at different times and in different places? The bank's original logs are like surveillance tapes all over the building, recording when and which key opened each door, how long it was open, and what was done inside. But there are too many tapes, piled up like mountains, and it would take several lifetimes for people to finish watching them all."

While rapidly typing on the keyboard and bringing up the necessary tool scripts, Liang Jiushan explained in a very fast voice: "My method is to design several filters. The first filter: time. After screening, retain all login records within half an hour before and after the time of the incident. The second filter: location. Lock down all terminal numbers and their associated servers that have undergone abnormal transfer operations. The third filter: and the most crucial one, abnormal keys. Specifically filter login behaviors that use high-privilege general accounts, default password accounts, or non-standard authentication protocols, especially those logins that occur when the terminal's physical location shows as idle, under maintenance, or even powered off."

He pressed the Enter key hard, and the screen instantly began to scroll through a dense stream of log entries at a dizzying speed.

Liang Jiushan stared intently at the screen, then turned to the technicians standing behind him: "It's a bit like using a program to quickly scan through a vast amount of surveillance footage, specifically picking out those times when no one should be working late at night, offices that should be locked or empty, where someone with a highly authorized master key that shouldn't be there brazenly opens the door. As long as they used a stolen key, they will definitely leave a mark on this footage!"

Everyone around got excited.

"Yes, yes, yes! It's the process of finding anomalies in the video recording."

"We used to rely on human eyesight, which was exhausting."

"It's like setting up a screening program on a computer, filtering layer by layer, and finally picking out the abnormal images."

Li Bin gestured a "shh" to the chattering crowd.

Everyone quieted down.

The only sounds in the office were Liang Jiushan's tapping on the keyboard and the others' breathless stares.

Li Zhenliang, Liu Haoran, and Zhou Wei also rushed over, their eyes fixed on Liang Jiushan's screen, which was constantly updating data. Although they didn't understand computers, they could sense Liang Jiushan's outstanding professional skills.

Now, Liang Jiushan is everyone's hope.

Jiang Ling stood to the side and slightly behind Liang Jiushan, her gaze calmly fixed on the rapidly scrolling screen.

She didn't understand the complicated instructions and parameters, but she saw Liang Jiushan's taut profile and the focused fire in his eyes. She saw the fine beads of sweat on his forehead, his knuckles that were slightly white from long hours of concentration, and the persistence and confidence that belonged to a technical talent.

Time passed second by second.

The data stream on the screen flowed like a raging river, breaching the invisible dam. Liang Jiushan frowned, his hands moving faster across the keyboard, constantly adjusting the filtering parameters and adding new selection criteria, trying to find clues from the massive amount of data.

“Too many… There are still too many login records that match the characteristics of ‘abnormal keys’… Most of them are illegal operations by bank employees trying to save trouble…” Liang Jiushan muttered to himself, his voice carrying a hint of barely perceptible anxiety.

He rubbed his sore eyes, took a deep breath, and forced himself to calm down.

Noticing that Liang Jiushan had slowed down, everyone dared not speak, for fear of disturbing his train of thought.

Jiang Ling pushed through the crowd and walked to Liang Jiushan's side. She bent down and whispered in his ear, "Jiushan, don't rush. Remember when we analyzed his operating habits? He always can't help but make small movements, trying to clean up, but he never does it perfectly. Could this psychological compulsion also manifest itself before he uses the electronic key to open the door? For example, after inserting the key into the lock, does he turn it left and right a couple of times to test if the key works? Or, like a thief who always likes to gently push the door before making a move to check the lock's status?"

Jiang Ling's words were like a ray of light flashing through the fog.

Liang Jiushan suddenly raised his head, his eyes gleaming: "Test the key? Yes! He might... he definitely will test it first! Test whether this stolen electronic key can be used at that time and on that terminal. Especially when he first uses a newly stolen high-privilege account, or switches to a new terminal. Such test logins are usually extremely brief, with a clear objective, merely verifying permissions without performing any substantive operations, and then immediately logging out, making them easy to overlook."

My mind suddenly clicked.

Liang Jiushan's fingers flew at an unprecedented speed, typing out a rapid series of commands on the keyboard. He restructured the filtering criteria.

Liang Jiushan knew why Jiang Ling had summoned him.

With the increasing application and widespread use of computers, this new type of crime will likely become more prevalent in the future. He not only needs to solve this problem, but also help more technical personnel update their knowledge and improve their skills. Therefore, solving this case requires not only action, but also communication and education for many others.

"We started searching again. In the short period before each confirmed ghost transfer or withdrawal occurred, we searched for extremely brief login records on the same terminal. After logging in, only a few basic query commands were performed, such as checking the time and checking one's own permission level, without any actual fund transactions, and then the user immediately logged out. This kind of record is like a thief secretly turning the doorknob before actually doing something, confirming that the lock is open, then retreating to the shadows to observe for a moment before actually taking action."

A new screening program has been launched.

This time, the screen scrolling seemed slower, but each refresh tugged at everyone's heartstrings. Liang Jiushan leaned forward slightly, his nose almost touching the screen, his eyes fixed intently on every suspicious record highlighted by the program.

Sudden!

The scrolling data on the screen suddenly stopped.

A record highlighted with a red border, like a glowing fish in the deep sea, suddenly appears frozen in the center of the screen.

Time: 3:05 PM, July 15th.

Terminal: Chengnan Branch, Training Room, Terminal Number: TRN_OLD_07, Status: Disabled, Pending Disposal.

Login account: sys_maint_bak.

Operation: Log in -> Execute command: show time -> Execute command: whoami -> Log out.

Duration: 9 seconds.

Immediately afterwards, at 3:11, the same TRN_OLD_07 terminal was logged in with a different high-privilege account and completed a transfer of 5,000 yuan, which was directed to Sun Ming's account.

"Found it!"

Liang Jiushan's voice trembled slightly with excitement as he pointed to the "test login" record that lasted only 9 seconds.

"Look here, that's it! TRN_OLD_07! In the training room of the Chengnan branch, there's an old terminal that should have been abandoned and discontinued long ago. Five minutes before he actually started transferring money, he logged in with a stolen high-privilege account, performed only two basic commands: confirmed the time and confirmed the current authorized user, and then immediately logged out. This is him testing the key; it's the trace he left before committing the crime."

The office fell into a deathly silence for a moment, followed by suppressed gasps and gasps.

Li Bin slammed his fist into his palm: "So it was hidden here! An abandoned training terminal, who would have thought?"

Li Zhenliang's face turned red with excitement: "That bastard has finally shown his true colors!"

Zhou Wei let out a long sigh of relief: "Good lad! You've really got it!"

Liu Haoran wanted to pat Liang Jiushan on the shoulder, but he was afraid that if he touched it, the things displayed on the computer would disappear, so he could only praise him by saying, "Well done, Jiushan."

Jiang Ling leaned down and stared at the highlighted record, which showed only 9 seconds.

“TRN_OLD_07…” Jiang Ling repeated the terminal number in a low voice, “Chengnan Branch Training Room, abandoned terminal.”

She sat up abruptly, raising her voice so loud it echoed throughout the office.

"Liangzi, thoroughly review the list of all technical and counter supervisors who have been dismissed or resigned from various banks in Yancheng in the past two years. Pay special attention to those who have worked at the Chengnan branch, especially those who have been in contact with the training system, equipment maintenance, or have high-level account management responsibilities. In particular, those whose reasons for leaving involve violations, system management conflicts, or strong dissatisfaction with the bank."

A burning fighting spirit ignited in Li Zhenliang's heart: "Yes!"

"Old Li, write down this crucial record. Immediately retrieve all physical access and maintenance records for this TRN_OLD_07 terminal over the past three months and find out who has access to it."

Li Bin nodded repeatedly: "Okay, okay, I'll do it right away."

"Haoran, notify Director Zhong and Team Leader Zhao to lock onto the target—the abandoned training terminal at the Chengnan branch. We've found that invisible hand!"

Liu Haoran stood at attention excitedly: "Yes!"

One command after another was issued by Jiang Ling, and everyone sprang into action.

Liang Jiushan remained seated in front of the computer, his fingers hovering above the keyboard, trembling slightly. It wasn't nervousness, but rather the lingering afterglow of immense excitement and a sense of accomplishment.

He looked up and met Jiang Ling's gaze.

In that gaze, there was undisguised admiration, the excitement of seeing the case solved, and a warm sense of affirmation. Jiang Ling said nothing, but simply reached out and pressed firmly and steadily on his shoulder.

The warmth and strength from that palm instantly dispelled all of Liang Jiushan's fatigue. He took a deep breath, straightened his back, and his fingers firmly landed on the keyboard again.

"Sister Ling, let me dig deeper into this account's login history and see where else he tried this key!" His voice regained its clarity, carrying the indomitable drive unique to young people.