ddos techniques

Detailed description of Linux iptables firewall + anti-DDOS policy configuration The network firewall function has been implemented in the Linux kernel for a long time. In different Linux kernel versions, different software is used to implement the firewall function.In the 2.0 kernel, the firewall tool is ipfwadm.In the 2.2 kernel, the firewall tool is ipchains.For kernels later than 2.4, the firewall operation tool is iptables. Ipfwadm and ipchains a

increasing the memory and modifying the number of maximum file descriptors (FD). So the question is, how is the DDoS attack going? Number of TCP semi-connections for DDoS attacks 　　In a DDoS attack, if the server allows a large number of TCP connections, server memory is very large, then the attacker is often to send a large number of TCP semi-con

DOS/DDOS Summary (This article is based on the online materials and the author's own understanding. It is only for learning and should not be used for illegal purposes. If your rights and interests are inadvertently infringed, please contact me in time. Thank you .) The structure of this article is as follows:I. Common DOS/DDOS types 1. Principle 2. symptom and Feature Detection 3. Prevention Ii. Some new t

The installation, configuration, and usage of the Apache anti-DDOS module mod_evasive were slow when a friend's website was accessed the previous day. The number of connections to the server was not large, and the resource usage was also small. if you suspect that there is an attack, install mod_evasive and try again. After the test, everything works properly. The installation configuration is as follows: wgethttp: www. zdziarski. comblogwp-contentupl

Major improvements of Tianying anti-DDOS firewall V1.78: protection against multiple SYN variants1. You can defend against Known DDOS, CC, DB, and legendary private servers without any configuration;2. The data analysis function is provided to defend against future attacks;3. Safe and efficient, with extremely low CPU usage;4. Remote connections are provided for ease of use;5. Defend against the latest SDDo

Eagle Anti-DDoS firewall V1.78 version major improvements: Increased number of SYN variant attack defense1. Without any configuration, can withstand the known ddos,cc,db, such as the attack of the legendary;2. With the data analysis function, can defend the future attack means;3. Safe and efficient, extremely low CPU usage;4. With remote connection, easy to use;5. Defense of the latest Sddos (super

Distributed denial of attack (DDOS) software tfn2k attack and defense First of all, the purpose of my writing this article is not what I want to be hacker and so on, and I do not encourage anyone to use it to do something detrimental to others, I just want one more Some people pay attention to network security, together research and defense of DOS. Because I was hurt by it: (, so, this article is only for technical reference, for you to study the us

1. Limit the number of IP connections to 80 ports to a maximum of 10, which can be customized. The code is as follows Copy Code Iptables-i input-p TCP--dport 80-m connlimit--connlimit-above 10-j DROP 2. Use the recent module to limit the number of new requests in the same IP time, recent more features please refer to: Iptables Module recent application. The code is as follows Copy Code Iptables-a input-p TCP--dpor

1, ensure the security of the server systemThe first step is to ensure that the server software does not have any vulnerabilities to prevent attackers from invading. Make sure the server is up to date with the latest system and security patches. Remove unused services on the server and close unused ports. For Web sites running on the server, make sure that they have the latest patches and no security holes.2. Hide the server real IPServer front-end plus CDN Transfer (free Baidu Cloud acceleratio

The main 2 basic practical applications, mainly related to the ban Ping (IPv4) and the prohibition of UDP, that is, the use of the server to prevent hackers to outsource DDoS attack content. First, if there is no iptables prohibit ping echo 1 >/proc/sys/net/ipv4/icmp_echo_igore_all #开启echo 0 >/proc/sys/net/ipv4/icmp_echo_igore_all #关闭Second, the use of iptables rules to ban ping Iptables-a input-p ICMP--icmp-type 8-s 0/0-j DROP Third, using the Ip

The Windows system itself has many mechanisms that can be used to improve performance and security, many of which can be used to cope with high concurrent requests and DDoS attacks. Windows Server performance can be improved with the following configurations: First, to respond to high concurrent requests: 1, TCP connection delay wait time TcpTimedWaitDelay: This is the time that must elapse before TCP/IP can release a closed connection and reuse i

The penalty policy for this attack is, Further violations would proceed with these following actions: 1st violation-warning and shutdown of server. We'll allow hours for your to rectify the problem. The first time is a warning + shutdown, give 24 hours to solve the problem 2nd violation-immediate reformat of server. The second time is to format the server immediately 3rd violation-cancellation with no refund. The third time is to cancel the service without giving a refund To address this pr

DoS (Denial of service denial-of-service) and DDoS (distributed denial of service distributed Denial-of-service) attacks are one of the security threats to large Web sites and network servers. The attacks on Yahoo, Amazon and CNN in February 2000 were carved into the history of major security events. Because of its good attacking effect, SYN Flood has become the most popular DOS and DDoS attack method at pr

DoS (Denial of service denial-of-service) and DDoS (distributed denial of service distributed Denial-of-service) attacks are one of the security threats to large Web sites and network servers. The attacks on Yahoo, Amazon and CNN in February 2000 were carved into the history of major security events. Because of its good attacking effect, SYN Flood has become the most popular DOS and DDoS attack method at pr

About the principle and defense of JS DDoS attacks Distributed Denial of Service (DDoS) attacks are the oldest and most common attacks against websites. Nick Sullivan is a system engineer at CloudFlare, a website acceleration and security service provider. Recently, he wrote an article about how attackers can use malicious websites, server hijacking, and man-in-the-middle attacks to initiate

apache program. Temporary directory of Lock Mechanism# WhitelistDOSWhiteList 127.0.0.1DOSWhiteList 192.168.12 .*If you do not know where to insert these data, you can use the following method;Create a file in the/etc directory, such as mod_evasive.conf;# Touch/etc/mod_evasive.confAdd the corresponding content according to your Apache version;Next, modify httpd. conf and add it to the last line.Include/etc/mod_evasive.confAfter modification, restart the Apache server;Service apachectl restart---

Mysterious little strong 1943 Squid is a port ing function that can be used to convert port 80. In fact, common DDOS attacks can be used to modify the parameters in/proc/sys/net/ipv4/tcp_max_syn_backlog, the default parameters are usually very small and set to more than 8000. Generally, DDOS attacks can be solved. If it reaches the timeout stage, set/proc/sys/net/ipv4/tcp_fin_timeout to a smaller value. E

To defend against DDoS is a systematic project, the attack pattern is many, the defense cost is high bottleneck, the defense is passive and helpless. DDoS is characterized by distributed, targeted bandwidth and service attacks, which are four-layer traffic attacks and seven-layer application attacks, corresponding to the defense bottleneck of four layers in bandwidth, seven layers of multi-architecture thro

), while facilitating user use, also created conditions for the emergence of large-volume DDoS attacks, as well as the need for device vendors and consumers to upgrade their security awareness, which contributed to DDoS amplification attacks. These aspects have led directly to the increase in DDoS risk.High-traffic attacks into the cloud, possible forms of cloud

Analysis of the method of using hash conflict vulnerability in PHP for DDoS attack This article mainly introduces the method that PHP uses the hash conflict vulnerability to carry out DDoS attack, and analyzes the principle and implementation technique of using hash for DDoS attack by PHP, and the Friends can refer to In this paper, we analyze the method of u