360 blockchain security

1. Private key~

2. Security in blockchain comes from some attributes< Mining blocks need to use resources< Br > 2. Each block contains the hash value of the previous block< Br > imagine if the attacker wants to change the chain by changing the transaction five blocks ago. If they tamper with the block, the hash value of the block changes. Then the attacker must change the pointer from the next block to the changed block, and then change the hash value of the next block... This will continue until the end of the chain. This means that the farther the block is behind the chain, the greater the resistance to change. In fact, the attacker has to simulate the hash capability of the whole network up to the front end of the chain. However, when the attacker tries to attack, the chain continues to move forward. If the attacker's hash value is lower than the rest of the chain (< 50%), they will always chase and never proce the longest chain. Therefore, this type of blockchain can resist attacks, where the attacker's hash value is less than 50%< Br > when attackers have 51% hash value, they can rewrite the network history with a list of valid transactions. This is because they can recalculate the hash value of any block sort faster than the rest of the network, so they can ultimately guarantee a longer chain. The main danger of 51% attacks is the possibility of double spending. This simply means that an attacker can buy an item and show that they have paid with any number of confirmations on the blockchain. Once they receive the item, they can reorder the blockchain so that it doesn't include the send transaction and get a refund< Br > even if the attacker has more than 50% hash value, the attacker can only do so much damage. They can't do things like transfer money from the victim's account to their account or print more coins. This is because all transactions are recorded by the account?? Account owners sign, so even if they control the entire network, they cannot forge account signatures.

3. Because each block contains its own hash value and the hash value of the previous block, changing a hash value will invalidate the rest of the blockchain
if you have problems with blockchain, you are welcome to chat in private~~~~~

4.

Recently, Vulcan team of 360 company found a series of high-risk security vulnerabilities in EOS, a blockchain platform. It is verified that some of the vulnerabilities can remotely execute arbitrary code on EOS nodes, that is, they can directly control and take over all nodes running on EOS through remote attacks

In the early morning of May 29, 360 reported this kind of vulnerability to EOS official for the first time, and assisted it to repair the security risks. The person in charge of the EOS network said that the EOS network will not be officially launched until these problems are fixed

EOS super node attack: the virtual currency transaction is completely controlled

in the attack, the attacker will construct and publish a smart contract containing malicious code, and the EOS super node will execute the malicious contract and trigger the security vulnerability. The attacker then uses the super node to pack the malicious contract into a new block, resulting in the remote control of all nodes in the network (alternative super node, exchange recharge withdrawal node, digital currency wallet server node, etc.)

because the system of the node has been completely controlled, the attacker can "do whatever he wants", such as stealing the key of the EOS super node and controlling the virtual currency transaction of the EOS network; Obtain other financial and privacy data in the participating node system of EOS network, such as digital currency in the exchange, user key stored in the wallet, key user information and privacy data, etc

What's more, an attacker can turn a node in the EOS network into a member of a botnet, launch a network attack, or become a free "miner" to extract other digital currency

source: Science and Technology News

5.

On June 8, 360 exposed the high-risk vulnerability of EOS, which caused a lot of hot discussion among networks. In the early morning of June 2, Beijing time, EOS officially acknowledged to the 360 security team and offered a reward of US $30000, strongly calling on the security community to work together to ensure the continuous improvement of EOS software security

360 exposed EOS vulnerability, if exploited, can control every node and every server in the EOS network, not only take over the virtual currency, various transactions and applications in the network, but also take over all participating servers in the node. It can be said that if someone makes a malicious smart contract, all the digital currencies in it can be taken away directly

the attack of EOS vulnerability can spread among multiple nodes and super nodes at the speed of seconds. The continuous propagation from the control node to the generation of new blocks is a continuous and chain explosion action. It is likely to take over all nodes and complete the operation in 20 seconds

imagine that when the attacker has obtained the supreme authority in the entire EOS network, it is equivalent to mieba putting together all six cosmic protoliths, and can change rapidly in the universe and do whatever he likes

source: China News

6. At present, many friends are in asproex (Apollo). The management of their family is composed of blockchain elites, bank executives and blockchain technology teams. They have rich experience in the blockchain instry and can learn more about it.

7. First of all, correct the problem. I feel it's a bit false. Has 360 really recruited most of these talents? Here's the answer: the main reason is Zhou Hongyi's quack atmosphere and sparing no effort to retain talents. People who do network security, especially those who do things like hacking, will have the flavor of the world. As long as the technology is good enough, Lao Zhou will spare no effort to stay and give a very free environment. On the other hand, 360's corporate culture: challenging giants and subverting rules. This kind of atmosphere will make technology makers feel very happy! View the original post & gt& gt;

8. Now 360 company is the largest Internet security company in China, full of strength

360 security software is used most frequently.

9. I don't recommend that you can use Jinshan to kill virus
mainly because 360 will track you all the way,
Jinshan won't, at least it hasn't been found yet

10.

It costs about 200 yuan to get the ring from the health care center

general hospitals need about 200 yuan, do a B-ultrasound examination and then remove the ring. If you want to remove the ring, it is recommended to go to a regular hospital to remove the ring. Generally speaking, you should exclude some contraindications of removing the ring. If you have fever, gynecological inflammation and other conditions, you need to control the condition before removing the ring

extended data:

the notes for ring taking are as follows:

have a good rest. After taking the ring, women should take a day off and get up again to avoid strenuous activities, such as doing heavy work. Avoid sex. After wearing the ring, you can't have sex for at least two weeks

bathing is prohibited. Women should not take a bath for two weeks after wearing the ring. Use contraception. If you wear a ring before menopause and don't want to get pregnant, you can use other contraceptive methods. Keep the vulva clean. Wash the vulva with clean water every night. Don't wash the vagina with your hands

generally, the ring should be removed 3-7 days after menstruation cleaning, and the gynecological color perspective or ring removal should be done to see the position of the ring. Observe your physical condition. After taking off the ring, please observe your health carefully. If you have fever, abdominal pain, bleeding and other abnormalities, you should see a doctor in time

References: network ring access