nmap显示奇怪的开放端口

在本地主机上运行nmap会显示奇怪的开放端口:

$ nmap -p- localhost Starting Nmap 6.47 ( http://nmap.org ) at 2015-12-28 12:14 CET Nmap scan report for localhost (127.0.0.1) Host is up (0.00047s latency). All 65535 scanned ports on localhost (127.0.0.1) are closed Nmap done: 1 IP address (1 host up) scanned in 2.51 seconds $ nmap -p- localhost Starting Nmap 6.47 ( http://nmap.org ) at 2015-12-28 12:14 CET Nmap scan report for localhost (127.0.0.1) Host is up (0.00046s latency). Not shown: 65533 closed ports PORT STATE SERVICE 36642/tcp open unknown 50826/tcp open unknown Nmap done: 1 IP address (1 host up) scanned in 2.55 seconds $ nmap -p- localhost Starting Nmap 6.47 ( http://nmap.org ) at 2015-12-28 12:14 CET Nmap scan report for localhost (127.0.0.1) Host is up (0.00050s latency). Not shown: 65531 closed ports PORT STATE SERVICE 37700/tcp open unknown 46694/tcp open unknown 48334/tcp open unknown 53438/tcp open unknown Nmap done: 1 IP address (1 host up) scanned in 2.60 seconds $ nmap -p- localhost Starting Nmap 6.47 ( http://nmap.org ) at 2015-12-28 12:14 CET Nmap scan report for localhost (127.0.0.1) Host is up (0.00046s latency). All 65535 scanned ports on localhost (127.0.0.1) are closed Nmap done: 1 IP address (1 host up) scanned in 2.51 second 

正如这个输出显示的那样,开放端口似乎变化快而且随机。 我不能通过netstat看到这些端口,如果我正确地解释输出:

 $ sudo netstat -tulpen Active Internet connections (only servers) Proto Recv-Q Send-Q Local Address Foreign Address State User Inode PID/Program name tcp 0 0 127.0.1.1:53 0.0.0.0:* LISTEN 0 17081 809/dnsmasq udp 0 0 0.0.0.0:5449 0.0.0.0:* 0 30885 2855/dhclient udp 0 0 127.0.1.1:53 0.0.0.0:* 0 17080 809/dnsmasq udp 0 0 0.0.0.0:68 0.0.0.0:* 0 30321 2855/dhclient udp 0 0 0.0.0.0:45170 0.0.0.0:* 107 15289 606/avahi-daemon: r udp 0 0 0.0.0.0:631 0.0.0.0:* 0 15931 636/cups-browsed udp 0 0 0.0.0.0:5353 0.0.0.0:* 107 15287 606/avahi-daemon: r udp6 0 0 :::34146 :::* 107 15290 606/avahi-daemon: r udp6 0 0 :::55654 :::* 0 30886 2855/dhclient udp6 0 0 :::5353 :::* 107 15288 606/avahi-daemon: r 

我试图用lsof来调查这些端口,但没有结果,我猜测当nmap返回时,端口不再打开:

 lsof -i :`nmap -p- localhost|grep '/tcp'|cut -d'/' -f1|head -n1` 

我能做些什么来进一步调查这个问题? 我必须担心吗? 这是正常的吗? 我应该怀疑有恶意进程在运行吗?

请注意,这个问答是不同的,因为我在我的本地机器上运行的一切。

这是Nmap 6.40 – 6.47中的一个bug,我在StackOverflow的一个答案中详细讨论过。 自从6.49BETA系列以来,它已经被固定下来,所以升级到最新的Nmap (本文写作时为7.01)将解决这个问题。