Security scanner for computers and networks.

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16
votes
3answers
32k views

How to find live hosts on my network?

I am trying to find the live hosts on my network using nmap. I am scanning the network in Ubuntu using the command sudo nmap -sP 192.168.2.1/24. However, i am unable to find the live hosts. I just get ...
10
votes
4answers
1k views

Is my network being sniffed?

Is there any way to find out if someone who is connected to my network is sniffing packets? There is a way with nmap if his card is in promiscuous mode but what if it is passive?
9
votes
4answers
2k views

nmap showing unknown IPs on private network

I had a go at scanning my home network with nmap, doing a 192.168.0.0/16 netscan. To my surprise, the results shown multiple live devices not only on 192.168.1.x (where all our known devices are) but ...
7
votes
5answers
4k views

How to detect hosts running in virtual machines with nmap?

I have to determine if a given subnet has virtual hosts. Are there any ideas about what switches to use?
6
votes
2answers
3k views

Scanning my network with NMAP

Each computer is assigned one ip address on my network, and my ISP supplies one IP for my network. If I try to scan the ip supplied by my ISP what I got is the OS running on the router, running on the ...
6
votes
4answers
489 views

Trying to firewall ports 1863, 5190

I'm using Debian's arno-iptables-firewall and I've configured it to only allow access on the ports I need. But nmap shows ports 1863, 5190 open. What gives? How can I interrogate those ports further? ...
5
votes
4answers
731 views

Persisting and comparing NMAP scans

Does anyone have any good recommendations on a good tool for persisting NMAP scans to database? It may be a tool for persisting or simply a java library for easy parsing of the nmap xml scan result ...
5
votes
2answers
508 views

How does nmap do a zombie and decoy scan?

We're learning nmap in my ethical hacking class. We got showed how we can use nmap to perform a zombie scan: nmap -PN -sI zombieIP targetIP and decoy scan: nmap -p 135 -D decoyIP targetIP I ...
5
votes
2answers
740 views

How can I use nmap to distinguish between a normal linux machine and an android device?

According to this link: here, nmap 5.2 onwards is now supposed to detect android smartphones. I am using nmap 6.01 but it only identifies android devices as running a linux kernel.
5
votes
1answer
851 views

How to use NMap to portscan a SonicWall that is blocking all attemtps?

It seems that SonicWall is blocking attemtps to scan its ports. I know it has some ports open, like 443, because if I access using the browser I get a web site. But when I try to use NMap I can't see ...
4
votes
3answers
5k views

How does “traceroute over TCP” work, what are the risks, and how can it be mitigated?

There is a utility called tcptraceroute, and this enhancement called intrace that is used just like a standard traceroute, but it works over TCP. How is the syn flag in TCP used to achieve ...
4
votes
5answers
708 views

How to bypass Nmap blockage?

I rent a server, and my provider seems to be blocking nmap. Is there any other tools I could use to test my home network from the outside? Also, does blocking nmap on a network provide any security? ...
4
votes
3answers
329 views

Are there any example domains where I can run my nmap scans just to learn?

I want to learn nmap and its various options. Are there any example domains which purposefully have security holes to facilitate learning nmap?
4
votes
4answers
971 views

How can I scan open ports without being traced back

I would like to scan open ports of a server. But as far as I know, when I try to scan the open ports with something like nmap in shell they would be able to trace me. Is there a way to secure this ...
4
votes
2answers
505 views

Detect what is running on an open port?

I have a wireless camera in my network. Running nmap on the camera, I discovered that the port 1010 is open but I could not find what it is used for. I looked in the administration pannel and did not ...
4
votes
3answers
576 views

Sharing Nmap scan results in a web page

Is there a tool that allow the sharing of nmap scan results ? I know nmap can produce XML and I can easily convert them in HTML. I would like to know if there is a tool with more features. For ...
4
votes
3answers
10k views

How to bypass tcpwrapped with nmap scan

I'd a scan task and I faced following result Host is up (0.032s latency). Scanned at 2012-10-25 16:06:38 AST for 856s PORT STATE SERVICE VERSION 1/tcp open tcpwrapped 3/tcp open ...
3
votes
2answers
287 views

Which ports are potential security risks for nmap?

I'm using nmap and I am having trouble finding which ports are dangerous and pose the greatest security risks. Which ports are potential security risks for nmap? I was thinking samba, telnet, vnc ...
3
votes
2answers
4k views

Could Nmap scan switches/routers

Nmap can scan and sometimes successfully detect the running OS in the remote host. However, can nmap scan routers and switches? Most of them use an embedded system.
3
votes
2answers
796 views

OS Fingerprinting for Android

Are traditional OS-fingerprinting techniques effective in identifying Android smartphones (OS version) on a network. From my research I found most Android network mappers can be only run from Android ...
3
votes
1answer
82 views

Use nmap correctly

I currently have a VPS in a data center, I asked the admin to open a port to install a ftp server. It opened port 3345, at first I tought the port is not forwarded correctly, because I ran nmap as ...
3
votes
1answer
2k views

Nmap scan produces all “unknown”

I scanned both localhost, and the IP address of the LAN adapter, and this is the produced output. Starting Nmap 5.51 ( http://nmap.org ) at 2012-10-12 18:06 Eastern Daylight Time Skipping SYN Stealth ...
3
votes
2answers
184 views

are there any services to test nmap

While playing with nmap, I have started to wonder: are there any ip addresses which were specifically made to learn how to use nmap. (As far as I understood I can not just scan any ip address, ...
3
votes
2answers
184 views

Determing live hosts past a restrictive firewall with nmap

Sometimes when I am doing an external security assesment, I run into hosts that have the following restrictions/configuration: All ICMP traffic is blocked An IDS or some device returns all ports as ...
3
votes
2answers
292 views

Why do multiple IP Addresses in my local network point to the same computer?

I'm new to linux and nmap, and I am attempting to do a scan of my local network. Using nmap I find that there are 4 hosts on my network (10.0.2.2, 10.0.2.3, 10.0.2.4, 10.0.2.15). I am using VirtualBox ...
3
votes
1answer
320 views

Is it possible to detect host-machine of my virtual-machines?

So basically I need to know is there any way to find a connection (or relation) between packets sent by my VMs and my host machine. In my lab I have lots of workstations, each running a VirtualBox ...
2
votes
5answers
479 views

OS fingerprinting: can I rely on the results?

Using nmap -O www.example.com I get: Running (JUST GUESSING): Microsoft Windows 7|2008 (90%) So I can say the target site is running Windows. Using xprobe2 -v www.example.com, I'm just astonished ...
2
votes
5answers
637 views

Nmap reporting almost every port as open

I have noticed during some assesments when doing a TCP port scan, Nmap will report almost every port as open for a machine. Using for example nmap -sS -PN -T4 target -p0-65535, over 20,000 ports will ...
2
votes
1answer
80 views

nmap: why is it “silly” to combine OS finding option (-O) with bounce scan (-b)

If you run an Nmap FTP bounce scan with nmap -O -b, nmap will do the scan, but it says that the scan "seems silly" before it starts. Why would the scan be silly? It actually appears to report a ton ...
2
votes
2answers
2k views

NMAP DNS Service Detection

I was looking out how NMAP identifies DNS services. After determining that port 53 is open it issues a standard query TXT version.bind to find out if BIND is running on the domain port. Then, I saw ...
2
votes
3answers
3k views

Why does an nmap -sT scan show ports filtered but -sS shows ports closed

What are possible reasons why an nmap -sT scan would show "ports filtered" but an identical nmap -sS scan shows "ports closed"? I understand that -sT is a full TCP Connect, which is easier to detect ...
2
votes
1answer
1k views

How can I see traceroute details in NMAP?

I'm using NMAP for Network scan ; The output does not contain the full traceroute details. Can I view all intermediate routers/hosts using the NMAP GUI? A simple VPN connection IP traceroute... ...
2
votes
1answer
384 views

Why are some ports reported as closed by nmap?

I was scanning a machine from inside the same LAN which is running and up to date Windows XP Home Edition which I suspect may be running some malware. The target machine has an up to date antivirus ...
2
votes
1answer
55 views

Does nmap limit probes when using time limiting on decoy scans?

If I set a rate limit (e.g. -T1) on an nmap scan that uses decoys, does the rate limit apply to all probes, or just each individual source? I checked the documentation, but can't see anything ...
2
votes
1answer
2k views

Scan multicast IP range on specific port using nmap

I'd like to scan a multicast IP range on a specific port using nmap. When I try to simply do a nmap -p 10000 239.35.0.0/16, it just responds with an error stating Strange error from connect ...
1
vote
3answers
739 views

How to find the OS of the target machine

I am new to this field. Currently I am using Linux OS and my question is how can I find the OS of another machine to which I do not have a direct access. I am interested in any possibilities which ...
1
vote
2answers
315 views

is it possible to test out remote host by using nmap?

I was trying to test out my friend's computer (with agreement) by using nmap remotely. But the result I got seems kinda awkward to me. It only showed 1900 as tcpwrapper and all other ports were no ...
1
vote
2answers
277 views

nmap no ping returns host is active and all ports are filtered

I am trying to determine if hosts are up. For hosts where a ping fails, I run a nmap (6.40) Regular and/or Quick scan. For a subset of my hosts, the nmap response is "Host seems down". As a follow up ...
1
vote
4answers
851 views

How to make nmap list an unfiltered port?

I have a host that is NAT'ed and I have opened a single port in my router so the host is reachable by the external world. I tested if it was reachable by running a service and connecting to it ...
1
vote
2answers
1k views

Found Unusual Services running on my VPS

I am running a Debian VPS and i did a port scan and found these services 135/tcp filtered msrpc 139/tcp filtered netbios-ssn 445/tcp filtered microsoft-ds 593/tcp filtered http-rpc-epmap 1720/tcp ...
1
vote
1answer
167 views

How does nmap determine if it's running HTTP service on a port? Fails here

I'm running apache on 192.168.56.178, which listens on port 80, 8090 and 8095 (configured as <VirtualHost *>). Now If I open my browser and point to any of those 3 ports, e.g ...
1
vote
3answers
112 views

Port Scanning Host that has Rate Limiting Enabled

I am trying to enumerate on of my lab machines. It seems that it has rate limiting enabled since I am getting blocked after the first few probes. I need to scan the whole 65535 tcp ports. I tried ...
1
vote
2answers
102 views

Correct way of establishing if the switch is sending syslogs?

I want to confirm through scanning means if the switch is sending syslog packets or not. What i did was run a nmap scan nmap -sV -p514 xxx.xx.xx.xx The result came out as closed. Does this ...
1
vote
2answers
85 views

NMAP SSMTP Service Detection

When I examined a NMAP -sV scan on a host running Exim on port 465, it uses the standard SYN scan to determine if the port is open, and then issues a Client Hello to which the server responds with a ...
1
vote
2answers
233 views

Changing IP ID generation of a server

I've seen plenty about Idle Scans and incremental IP IDs on the net, but I have trouble finding a "solution" to the problem. Is there a way to "set" IP IDs for example to all zeros or is it coded into ...
1
vote
1answer
36 views

Scan All private subnets with NMAP [closed]

I have a managed switch on my network but I don't remember the subnet. How can I scan all the private network without changing my ip address : 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16 Thanks for ...
1
vote
4answers
106 views

Comprehensive audit of firewall - is Internet truly not accessible?

We have many Linux servers in several co-locations over the world. By design, these machines generally should not be able to access the Internet. Depending on location and role, some sites may have ...
1
vote
2answers
591 views

How do I find a target on the wired network, from an attack system on Wi-Fi?

I'm trying to practice penetration testing on my home network. The target system is my desktop computer, which is connected to the network via ethernet cable. The attack system is my laptop, which is ...
1
vote
1answer
419 views

What are the best Nmap Scripting Engine (NSE) service discovery scripts? [closed]

Using nmap -sV can be quite verbose can -sU can take a very long time especially with -p 0-65535. To narrow your results and enumerate interesting services the wealth of NSE scripts can be very ...
1
vote
1answer
1k views

Nmap port scan and FTP bounce

Suppose that there is a network of machines, and there is a server with ftp server that allows ftp bounce. I do a nmap scan on the network nmap -sC -some other parameters network address. Does nmap ...