Chapter 104 The result that shocked the cryptography experts

Xu Yuan is very familiar with the entire process of cracking the MD5 password. He does not even need to prepare anything specially when giving a report on stage. He is confident that he can give a surprise to cryptography experts around the world.

8 month 17 day.

on Tuesday.

The main lecture hall of the International Cryptography Conference.

nine in the morning.

A total of three hundred cryptography experts attended the meeting.

But perhaps because yesterday was rather dull, many people seemed to have no interest.

Until the host comes on stage to announce the next report participants and content.

"The first report this morning was made by a research team from Huaguo Qinghua University and Qilu University. Their paper was about cracking the MD5 encryption algorithm."

After finishing his work, the host walked directly to the stage, leaving the podium to the person who was about to give a report.

Little did they know that this sentence instantly caused an uproar in the lecture hall, and everyone looked up as if they were resurrected.

Unexpectedly, on the second day of the conference, someone attacked the uncrackable MD5 password algorithm.

There was so much discussion in the audience.

"This is really good news. Someone is challenging this almost impossible-to-beat existence again."

"The MD5 cryptographic algorithm is unbreakable."

"I know Qinghua University. When did they train hash function cryptographers? Don't they know that cracking the MD5 cryptographic algorithm is a very stupid and arrogant decision?"

"It seems that after today, the cryptography community will have another joke."

"Whatever the result, they deserve admiration for having the courage to challenge the MD5 password."

……

For them, they had never heard of any cryptography experts in these two universities from Eastern countries, so it was too arrogant to crack the MD5 password at this level.

In addition to wasting a lot of time, it will also become a laughing stock at this international cryptography conference.

Even Professor Biham, who was sitting in the front row, seemed to be recalling the previous attempt to crack MD5.

Regret and resentment appeared on his face.

It can be said that cracking the MD5 password algorithm is his lifelong dream.

Ever since Turing Award winner Rivest designed MD5, he began researching to find loopholes. Unfortunately, he has been working on this problem for more than ten years without any breakthrough results.

Later, we had to give up studying hash functions and acknowledge the security of the MD5 cryptographic algorithm.

Every time I think about it now, I am still filled with regret.

He naturally hopes to see someone successfully crack MD5, but there is always a huge gap between dreams and reality.

Just as he was thinking about this, Desmed, who was sitting next to him, suddenly leaned his head over, and the injury on his arm did not affect the smile on his face at all.

"Professor Biham, what do you think of today's report? It's been a while since anyone has tried to crack MD5."

"They have undoubtedly given themselves a difficult task." Biham replied solemnly after hearing his old friend's words: "I don't think there is anything worth paying attention to in this report."

"I agree with you." Desmed nodded.

Xu Yuan naturally heard the discussions of the cryptographers on the scene, but it did not affect him.

He stood up and signaled to Wang Xiaoyun and the others, then walked towards the stage with confidence.

In the main lecture hall of the International Cryptography Conference, in addition to the screen at the back, there is also a place to place a computer next to the podium, which makes it convenient for the speaker to use the computer for operation demonstrations.

Just like the last time he attended the number theory academic conference, Xu Yuan still did not bring any speech manuscripts this time.

After all, the relevant papers will be displayed on the screen.

However, before he officially began his speech, he heard a new round of conversation among the cryptographers in the audience.

If he just looked down on the report and didn't think it had any content, now he was a little angry and expressed dissatisfaction with Wang Xiaoyun's team for letting a student who looked so young to give a report on stage.

Originally, no one believed that this paper could play any substantial role in cracking MD5.

Now that the speaker is a student, I naturally have less expectations for the first report in the morning.

"Why is it that a student is giving a report on stage? China really doesn't have many people in the field of cryptography."

"The content of today's meeting was truly disappointing."

“I can’t imagine how many mistakes there are in this paper, even for a project that students can participate in.”

"These are going to be the most pointless two hours I've ever spent."

……

Although Xu Yuan couldn't hear clearly what the cryptographers in the audience were saying, he could guess a little.

It is nothing more than questioning the report he made when he took office.

He chose to ignore it all, with a smile that showed he was confident he was in control of the situation, and started reporting at his own pace.

As he officially opened his mouth and got to the point, the audience finally quieted down and maintained order at the conference.

"Ladies and gentlemen, today I will present a paper report on the cracking of the MD5 message digest algorithm. After research by me and my team, we have determined that this algorithm has loopholes and can be cracked."

"Next, I will explain in detail the research process and the steps to crack the MD5 algorithm." There is no doubt that when Xu Yuan's words reached every corner of the lecture hall, almost everyone's face showed surprise.

I never expected that someone would dare to say that they cracked the MD5 password.

What kind of existence is MD5?

Many international cryptographers have been studying it for more than ten years but are still helpless. How could it be cracked by an unknown small team?
This is obviously impossible.

Therefore, there is only one true situation, that is, the other party deliberately falsified information to attract attention.

However, no one spoke out to stop them from continuing to talk. Instead, everyone had a sneer on their face, looking like they were waiting to see a good show. They all believed that after today, the biggest joke in the history of cryptography would be born.

But as time passed, when Xu Yuan talked about the new differential collision method and the nearly three hundred sufficient conditions for collision, the audience began to get restless.

Biham was the first to react, and he was attracted by the collision method mentioned in the paper.

His gaze towards the stage became more focused, completely devoid of the contempt and disdain he had just shown; he was like a completely different person.

While he was whispering softly, his eyes became brighter and brighter, as if he had discovered an inestimable precious treasure.

"This is an optimized differential collision..."

“It’s just so exquisite.”

"What kind of genius cryptographer could come up with this collision method?"

Desmed, who was sitting next to him, was not in much better condition either. With his injured arm, he used his other hand to calculate on his seat, and a bold guess emerged uncontrollably in his mind.

“Is it true that the MD5 password has been cracked?”

Although he firmly told himself that this was impossible, the content of the paper continued to stimulate him.

All present were internationally renowned cryptography experts, and they could naturally tell whether the content of the paper was valuable or not. Therefore, just twenty minutes into the report, everyone realized that they had made a wrong judgment.

Although this research team from China is not well-known, their level is no worse than that of the world's top cryptographers.

Just based on the collision method mentioned in the paper, even if it ultimately fails to successfully crack MD5, it is enough to be called the highest quality paper of this conference so far.

Then a very interesting scene appeared in the lecture hall. The cryptographer, who had been waiting to see the joke with disdain, suddenly discovered that he was the biggest joke.

But it must be said that Xu Yuan's report aroused everyone's interest, and in the end everyone was even filled with anticipation.

I hope that today we can see a miracle in the history of cryptography and successfully crack the MD5 cryptographic algorithm.

At this point, no one cared that the person reporting on the stage was just a young man who looked like a student.

As long as you can see the end result, it will all be worth it.

It is also worth mentioning that at this moment there are still people in the main lecture hall with disdain on their faces.

They are officials from the Bureau of Standards and Technology.

"Don't worry, Mr. Lehman. Our MD5 password was designed by Professor Rivest himself. No one in the international cryptography community has been able to crack it in more than a decade."

"This has proven the security of the MD5 password and there is absolutely no possibility of a loophole."

"The other research team is just a newcomer in the field of cryptography. Two of the members are even students."

"Their research results must be wrong. I can guarantee you 100% of that."

Lehman, who was the head of the Standards and Technology Bureau and was sitting in the front seat, just waved his hand after hearing what his subordinates said.

"I'm certainly not worried about anything. They can't crack the MD5 password even if they have a million years."

They maintained absolute confidence from beginning to end and did not believe that anyone could crack their MD5 password, let alone someone they had never heard of.

Even Professor Biham, a world-renowned top cryptography expert, considers his failure to crack MD5 as his biggest regret in life, not to mention other scholars in the field of cryptography.

……

"The above are all the steps to crack the MD5 password. When sufficient conditions are met, our cracking algorithm can successfully complete the collision of the results."

After finishing the one and a half hour long report, Xu Yuan raised his head and looked down at the audience with a relaxed look.

It was discovered that only Wang Xiaoyun and a few others were clapping sporadically, while the other cryptography experts were all busy verifying.

You can vaguely see the excitement on his face.

After listening to the entire report, they also felt that there was great hope this time, and perhaps MD5 had been successfully cracked, so they all wanted to verify the results as soon as possible.

In the lecture hall that could hold 300 people, no one spoke.

Although Xu Yuan was very happy to see this scene, the embarrassing thing was that he didn't know whether he should go down or not.

Just as I was hesitating, the host came on stage to remind me.

"The next report will begin soon. Please pay attention to the time."

"Ok."

When Xu Yuan heard this, he did not hesitate. After he understood it, he prepared to step down and finish his report.

But just as he was about to take a step, he saw Professor Biham in the front row suddenly stand up and say loudly in English: "Move the next report to the spare room. Anyone who wants to listen to the next one can go over."

"Now the report continues."

As soon as he finished speaking, he quickly sat down and continued to verify. As for the host, he had to hurriedly go off the stage to make arrangements.

(End of this chapter)