端口_139_445_等端口的作用（The role of _139_445_ and other ports）

_139_445_等端口的作用The role of_139_445_andotherportspropose a thesis and expound its feasibility

For example, port 80 for web communications and 110/25 portsfor SMTP allow access from specified addresses, and all otherports and addresses can be closed. Most networks will enjoyacceptable security levels by using the "rejection requestfiltering" scheme. When you use this filtering policy, you canblock your network does not use the port and Troy Trojan orinvestigation of commonly used ports to enhance your networksecurity. For example, blocking 139 ports and 445 (TCP and UDP)ports will make it harder for hackers to execute exhaustiveattacks on your network. Blocking 31337 (TCP andUDP) ports willmake it harder for Back Orifice Trojan programs to attack yournetwork. This work should be defined in the network planningphase, at this time the security level should be in line withthe needs of network users. Look at the list of these ports tounderstand the normal use of these ports.

Common port control port: 0

Services: Reserved

Explanation: usually used to analyze XX as a system. This methodworks because in some systems, "0" is an invalid port, and whenyou try to connect it with the usual closed port, differentresults will be produced. A typical scan, using IP address as

0.0.0.0, setting ACK bits and broadcasting on Ethernet layer.Port: 1

Services: tcpmux

Explanation: This shows that someone is looking for SGI Irixmachines. Irix is the primary provider of tcpmux, and by default,tcpmux is opened in this system. Irix machines are issued withseveral default password free accounts, such as: IP, GUEST UUCP,NUUCP, DEMOS, TUTOR, DIAG, OUTOFBOX, et c. . Many admini stratorsforget to delete these accounts after installation. So HACKERsearches for tcpmux on INTERNET and takes advantage of theseaccounts.

Port: 7

Services: Echo

Explanation: you can see the information sent to X.X.X.0 and

X.X.X.255 when many people search for Fraggle amplifiers.Port: 19

Services: Character Generator

Explanation: This is a service that sends only characters. TheUDP version will respond to a package containing spamcharacters after receiving the UDP package. The TCP connectionsends a data stream containing garbage characters until theconnection is closed. HACKER uses IP spoofing to launch DoSattacks. Forge UDP packages between two chargen servers.Similarly, the Fraggle DoS attack broadcasts a packet of forgedvictim IP to the port of the target address, and the victim isoverloaded to respond to the data.

Port: 21

Services: FTP

Description: FTP server openport for uploading and downloading.The most common attackers are looking for ways to open anonymousFTP servers. These servers have readable directories. TrojanDoly Trojan, Fore, Invisible FTP, WebEx, WinCrash and BladeRunner open ports.

Port: 22

Services: Ssh

Explanation: the connection between the PcAnywhere and the portestablished by TCP may be to find ssh. This service has manyweaknesses, and if configured to a specific pattern, manyversions of using the RSAREF library will have a lot ofloopholes.

Port: 23

Services: Telnet

Explanation: remote login, intruder in search of remote loginUNIX service. In most cases, this port is scanned to find themachine running XX as a system. And with other technologies,intruders can find passwords. Trojan Tiny Telnet Server opensthis port.

Port: 25

Services: SMTP

Explanation: the port opened by the SMTP server is used to sendmail. Intruders look for SMTP servers to pass on their SPAM.The intruders' accounts are closed, and they need to connectto the high bandwidth E-MAIL server and send simple messagesto different addresses. Trojan horse Antigen, Email PasswordSender, Haebu Coceda, Shtrilitz Stealth, WinPC, WinSpy all openthis port.

Port: 31

Services: MSG Authentication

说明木马大师天堂、黑客天堂开放此端口。

端口 42

服务 WINS复制

说明胜复制

端口 53

服务域名服务器DNS

说明 DNS服务器所开放的端口入侵者可能是试图进行区域传递

TCP欺骗或隐藏其他的通信因此防火墙常常过滤或记录此端口DNS UD P。

端口 67

服务 引导协议服务器

说明通过DSL调制解调器的防火墙常会看见大量发送到广播地址的数据和255.255.255. 255。这些机器在向DHCP服务器请求一个地址。黑客常进入它们分配一个地址把自己作为局部路由器而发起大量中间人中间人攻击。客户端向68端口广播请求配置服务器向67端口广播回应请求这种回应使用广播是因为客户端还不知道可以发送的IP地址。

端口 69

服务简单文件传输

说明许多服务器与BOOTP一起提供这项服务便于从系统下载启动代码。但是它们常常由于错误配置而使入侵者能从系统中窃取任何文件。它们也可用于系统写入文件。

端口 79

服务指服务器

说明入侵者用于获得用户信息查询XX作系统探测已知的缓冲区溢出错误 回应从自己机器到其他机器手指扫描。

端口 80

服务 http

说明用于网页浏览开放此端口木马遗嘱执行人。

端口 99

服务 Metagram Relay

说明后门程序程序ncx99开放此端口。

100 ------- 1000

端口 102

服务 邮件传输代理MTA在TCP / IP -x.400

说明消息传输代理。

端口 109

服务 邮局协议-电力工程协会

说明 P OP3服务器开放此端口用于接收邮件客户端访问服务器端的邮件服务。 POP3服务有许多公认的弱点。关于用户名和密码交换缓冲区溢出的弱点至少有20个这意味着入侵者可以在真正登陆前进入系统。成功登陆后还有其他缓冲区溢出错误。

端口 110

服务太阳公司的RPC服务所有端口

说明常见RPC服务有RPC。装好、 NF S、 RP C。态、 RP C。 CS MD、 RPC。t t yb d、 AMD等

端口 113

服务认证服务

说明这是一个许多计算机上运行的协议用于鉴别TCP连接的用户。使用标准的这种服务可以获得许多计算机的信息。但是它可作为许多服务的记录器尤其是FTP、流行、 IMAP、 SMTP和I RC等服务。通常如果有许多客户通过防火墙访问这些服务将会看到许多这个端口的连接请求。记住如果阻断这个端口客户端会感觉到在防火墙另一边与电子邮件服务器的缓慢连接。许多防火墙支持连接的阻断过程中发回这将会停止缓慢的连接TCP RST。

端口 119

服务 网络新闻传输协议

说明新闻新闻组传输协议承载Usenet通信。这个端口的连接通常是人们在寻找Usenet服务器。多数ISP限制只有他们的客户才能访问他们的新闻组服务器。打开新闻组服务器将允许发/读任何人的帖子访问被限制的新闻组服务器匿名发帖或发送垃圾邮件。端口 135

服务位置服务

说明微软在这个端口运行DCE RPC终点马你好二为它的服务这与UNIX 111端口的功能很相似DCOM。

Using DCOM and RPC services, use the end-point Ma Hello Er onyour computer to register their locations. When the remote

client connects to the computer, they look for end-point MaHello Er to find the location of the service. Is the port ofthe HACKER scan computer to find the Exchange Server runningon this computer?What version?There are also some DOS attacksdirected directly at this port.

Ports: 137, 138, 139

Services: NETBIOS Name Service

Explanation: 137 and 138 are UDP ports, which are used whentransferring files through the network neighbor. And the 139port: the connection entered through this port tries to getNetBIOS/SMB service. This protocol is used for windows file andprinter sharing and SAMBA. And WINS Regisrtation uses it too.Port: 143

Services: Interim Mail Access Protocol V2

Explanation: like the security problems of POP3, there arebuffer overf low vulnerabilities in many IMAP servers. Remember:a LINUX worm (admv0rm) wil l propagate through this port, so manyof the ports are scanned from unsuspecting users who have beeninfected. These vulnerabilities become very popular whenREDHAT defaults to IMAP in their LINUX release. This port isalso used in IMAP2, but it' s not popular.

Port: 161

Services: SNMP

Explanation: SNMP allows remote management of devices. Allconfiguration and operation information is stored in thedatabase, and this information can be obtained through SNMP.Many administrators' error configurations will be exposed toInternet. Cackers will attempt to access the system using thedefault password public and private. They may try all possiblecombinations. The SNMP packet may be mistakenly pointing to theuser' s network.

Port: 177

Services: X Display Manager Control Protocol

Explanation: many intruders access it via X-windowsxx, and italso needs to open 6000 ports.

Port: 389

Serv ice s: LDAP, ILS

Description: light directory access protocol and NetMeetingInternet Locator Server share this port.

Port: 443

Services: Https

Explanation: the web browser port provides another kind of HTTPthat encrypts and transfers through secure ports.