Question 1:

Snort Rules

Scenario

A small company has a network set up behind a NAT router. The router is connected to the Internet via a single ISP provided dynamic IP address. The ISP provided access address may change over short periods of time.

The internal network is RFC 1918 Category 2 compliant, and uses the private address space 192.168.2.0/24. The gateway router is configured to use DHCP allocated IP addresses to internal hosts as they connect. However, a record is kept within the router of what IP addresses have previously been allocated to specific MAC addresses. Whenever those MAC addressed hosts disconnect from and later reconnect to the network they are reallocated the same IP address. It is only if the router has a power off episode, or is manually reset, that allocation of different IP addresses may occur (and even then, the same addresses may be allocated as before).

The company operates an approved internal web server at 192.168.2.21:80, to facilitate in-house development of web pages and web sites that will later be deployed to an external server for public access. It is a company policy that only one approved internal web server is to be in operation on the network.

It has come to the notice of the IT manager that a company employee has set up a rogue web server on the internal network, using a personal laptop. The employee is using that web site to provide undesirable material to a small clique of employees, to whom the web server address has been provided secretly.

Considerations

- The rogue web server may be on any internal IP address, and will be using any of the ephemeral ports. It will not be using a well-known port.
- The clients accessing the rogue web server may come from any internal IP address using any ephemeral port.
- The MAC addresses of all company host devices are on record.

Your job

Use snort to monitor for any internal network HTTP traffic destined for any internal host on any port address other than the authorised company internal web server and produce an alert message.

You are to write a .conf file containing the snort rule(s) that will accomplish a solution and run it against the pcap file provided.

The snort monitoring will identify when breaches have occurred. The Wireshark pcap file containing the captured packets can be time correlated with the logged snort alerts to obtain MAC addresses for source and target.

If your rule is correct the alert.ids file will show entries like the following:

[**] [1:1000010:1] Unauthorised HTTP traffic [**]
[Classification: ] [Priority: 1]
09/12-19:10:29.439844 192.168.2.5:49496 -> 192.168.2.2:6400
TCP TTL:64 TOS:0x0 ID:18940 IpLen:20 DgmLen:408 DF
***AP*** Seq: 0xE8349C5 Ack: 0xBCB171EE Win: 0xFFFF TcpLen: 32
TCP Options (3) => NOP NOP TS: 1210791384 0

[**] [1:1000010:1] Unauthorised HTTP traffic [**]
[Classification: ] [Priority: 1]
09/12-19:10:29.440554 192.168.2.2:6400 -> 192.168.2.5:49496
TCP TTL:128 TOS:0x0 ID:1065 IpLen:20 DgmLen:1300 DF
***A**** Seq: 0xBCB171EE Ack: 0xE834B29 Win: 0xFE9B TcpLen: 32
TCP Options (3) => NOP NOP TS: 195453 1210791384

[**] [1:1000010:1] Unauthorised HTTP traffic [**]
[Classification: ] [Priority: 1]
09/12-19:10:29.449929 192.168.2.5:49496 -> 192.168.2.2:6400
TCP TTL:64 TOS:0x0 ID:18942 IpLen:20 DgmLen:367 DF
***AP*** Seq: 0xE834B29 Ack: 0xBCB1799C Win: 0xFFFF TcpLen: 32
TCP Options (3) => NOP NOP TS: 1210791384 195453

[**] [1:1000010:1] Unauthorised HTTP traffic [**]
[Classification: ] [Priority: 1]
09/12-19:10:29.450478 192.168.2.2:6400 -> 192.168.2.5:49496
TCP TTL:128 TOS:0x0 ID:1067 IpLen:20 DgmLen:485 DF
***AP*** Seq: 0xBCB1799C Ack: 0xE834C64 Win: 0xFD60 TcpLen: 32
TCP Options (3) => NOP NOP TS: 195453 1210791384

[**] [1:1000010:1] Unauthorised HTTP traffic [**]
[Classification: ] [Priority: 1]
09/12-19:10:43.904673 192.168.2.5:49496 -> 192.168.2.2:6400
TCP TTL:64 TOS:0x0 ID:18947 IpLen:20 DgmLen:451 DF
***AP*** Seq: 0xE834C64 Ack: 0xBCB17B4E Win: 0xFFFF TcpLen: 32
TCP Options (3) => NOP NOP TS: 1210791413 195509

[**] [1:1000010:1] Unauthorised HTTP traffic [**]
[Classification: ] [Priority: 1]
09/12-19:10:43.913290 192.168.2.5:49497 -> 192.168.2.2:6400
TCP TTL:64 TOS:0x0 ID:18950 IpLen:20 DgmLen:451 DF
***AP*** Seq: 0xBF45540D Ack: 0xBEFA2FE2 Win: 0xFFFF TcpLen: 32
TCP Options (3) => NOP NOP TS: 1210791413 0

[**] [1:1000010:1] Unauthorised HTTP traffic [**]
[Classification: ] [Priority: 1]
09/12-19:10:43.913886 192.168.2.2:6400 -> 192.168.2.5:49497
TCP TTL:128 TOS:0x0 ID:1071 IpLen:20 DgmLen:571 DF
***AP*** Seq: 0xBEFA2FE2 Ack: 0xBF45559C Win: 0xFE70 TcpLen: 32
TCP Options (3) => NOP NOP TS: 195597 1210791413

[**] [1:1000010:1] Unauthorised HTTP traffic [**]
[Classification: ] [Priority: 1]
09/12-19:10:43.919054 192.168.2.5:49498 -> 192.168.2.2:6400
TCP TTL:64 TOS:0x0 ID:18956 IpLen:20 DgmLen:365 DF
***AP*** Seq: 0x18030D8E Ack: 0xCFE60A18 Win: 0xFFFF TcpLen: 32
TCP Options (3) => NOP NOP TS: 1210791413 0

[**] [1:1000010:1] Unauthorised HTTP traffic [**]
[Classification: ] [Priority: 1]
09/12-19:10:43.946959 192.168.2.2:6400 -> 192.168.2.5:49498
TCP TTL:128 TOS:0x0 ID:1075 IpLen:20 DgmLen:660 DF
***AP*** Seq: 0xCFE60A18 Ack: 0x18030EC7 Win: 0xFEC6 TcpLen: 32
TCP Options (3) => NOP NOP TS: 195598 1210791413

[**] [1:1000010:1] Unauthorised HTTP traffic [**]
[Classification: ] [Priority: 1]
09/12-19:11:11.614057 192.168.2.3:1923 -> 192.168.2.2:6400
TCP TTL:128 TOS:0x0 ID:44619 IpLen:20 DgmLen:496 DF
***AP*** Seq: 0xC9090643 Ack: 0x550D4778 Win: 0xFFFF TcpLen: 20

[**] [1:1000010:1] Unauthorised HTTP traffic [**]
[Classification: ] [Priority: 1]
09/12-19:11:11.656165 192.168.2.2:6400 -> 192.168.2.3:1923
TCP TTL:128 TOS:0x0 ID:1079 IpLen:20 DgmLen:230 DF
***AP*** Seq: 0x550D4778 Ack: 0xC909080B Win: 0xFE37 TcpLen: 20

[**] [1:1000010:1] Unauthorised HTTP traffic [**]
[Classification: ] [Priority: 1]
09/12-19:11:19.504867 192.168.2.3:1926 -> 192.168.2.2:6400
TCP TTL:128 TOS:0x0 ID:44648 IpLen:20 DgmLen:450 DF
***AP*** Seq: 0xEC018654 Ack: 0x5E762A07 Win: 0xFFFF TcpLen: 20

[**] [1:1000010:1] Unauthorised HTTP traffic [**]
[Classification: ] [Priority: 1]
09/12-19:11:19.540195 192.168.2.2:6400 -> 192.168.2.3:1926
TCP TTL:128 TOS:0x0 ID:1082 IpLen:20 DgmLen:555 DF
***AP*** Seq: 0x5E762A07 Ack: 0xEC0187EE Win: 0xFE65 TcpLen: 20

[**] [1:1000010:1] Unauthorised HTTP traffic [**]
[Classification: ] [Priority: 1]
09/12-19:11:19.550534 192.168.2.3:1926 -> 192.168.2.2:6400
TCP TTL:128 TOS:0x0 ID:44650 IpLen:20 DgmLen:451 DF
***AP*** Seq: 0xEC0187EE Ack: 0x5E762C0A Win: 0xFDFC TcpLen: 20

[**] [1:1000010:1] Unauthorised HTTP traffic [**]
[Classification: ] [Priority: 1]
09/12-19:11:19.590606 192.168.2.2:6400 -> 192.168.2.3:1926
TCP TTL:128 TOS:0x0 ID:1083 IpLen:20 DgmLen:792 DF
***AP*** Seq: 0x5E762C0A Ack: 0xEC018989 Win: 0xFCCA TcpLen: 20

Note: The classification identifier has been deleted.

Tips:

- You will need to familiarise yourself with the HTTP header contents. You need to identify some text pattern in the HTTP header that will unambiguously indicate whether a client is accessing a web server, or vice versa. (remember, the rogue web server is operating on a non-standard ephemeral port.)

- Make sure you include the standard Snort classtypes in your rule. Refer to the SNORT documentation to determine which classtype is appropriate for this exploit as described above. You will probably have to make use of the classification.config file (located in the Snort\etc\ directory) - research how to make reference to this file from your rules file.

- Failure to use the correct syntax in your rule will mean the rule is ineffective. This means you will lose marks on this question.

Note: Duplicating the contents from the text, lecture slides, weekly notes or the Internet is not acceptable (even if it is referenced) and will not attract any marks. Your solutions must be written in your own words. If you cannot write your answer in your own words, then you have not yet mastered the topic and require further reading or advice from your tutor. Any information taken from an external source (either from the textbook or any other source) must be referenced appropriately. Failure to do so constitutes plagiarism.

a) Identification of Addresses

By inspecting the alert.ids entries you should be able to identify:

1. The IP address, and port number of the device hosting the rogue web server.
2. The IP addresses and port numbers of all devices that have accessed the rogue web server.

You are to enter this information into the table following

Explain in your own words how the MAC addresses of these devices can be discovered from the pcap file.

Question 2:

Certificates

A. Because there are multiple certificate authorities (CAs) for the Web PKI it is possible to buy multiple certificates for the same domain signed by different CAs. How would a browser treat these different certificates?

B. ) Suppose that an imposter is able to obtain a certificate for a domain that the imposter doesn't own. (For example, in January 2001, an imposter tricked VeriSign into signing two certificates for "Microsoft Corporation" to be used for signing new software to be installed.) What sorts of attacks could an imposter pull off once in possession of such "fake" certificates for i. installing software.

ii. Viewing Web pages

C Typically the public SSH keys used by servers are not signed by any certificate authority, but the SSH protocol does support checking certificates.

i. Why, in practice, are server certificates rarely signed?

ii. What is the benefit of checking server certificates?

Question 3:

Firewall Rules

Assume you have the following firewall rules:

a) Define what a rule conflict is and Identify any conflicts.

b) Identify any redundancies and explain which rule would be applied using each of the following 3 matching strategies:
1. FIRST
2. BEST
3. LAST

Question 4:

Firewalls

a) What is a proxy firewall and how is it different from a network (or transparent) firewall?

b) What does NAT stand for, and how does the mechanism work? Describe what, if any, security NAT provides (or fails to provide).

c) Where would you place a web server in an organization assuming that you can use a network firewall and why?

Question 5

You are the Chief Information security Officer (CISO) of a small medium sized - accounting Services Company. In the last few weeks, senior staff have been complaining that some confidential information has been disclosed via email without any authorisation. You are approached by the Chief Information Officer (CIO) to discuss the issue and see the most appropriate way to tackle this problem. You suspect that some of the employees might be using their technical skills to access sensitive information either from the mail servers or during transmission. To counteract this malpractice, you suggest to the CIO the implementation of encryption. Before you actually implement the system, you want to conduct a pilot using the GNU Privacy Guard (GPG) software.

The pilot requires that you install GNU Privacy Guard (GPG) software onto your own computer and complete the following activities.

Note: The GNU Privacy Guard is available for free download from http://www.gnupg.org/ and "A Practical Introduction to GNU Privacy Guard in Windows" by Brendan Kidwell is available at http://www.glump.net/howto/gpg_intro

After installing GPG software onto your own computer, complete the following tasks:

1. Generate your own key-pair by using GPG software and do not create a pass-phrase for your private key (in a real world this is not a good practice. Just for the sake of this assignment, do not create a pass-phrase). You must use screen-shots to show that you have successfully completed this task. A valid screen-shot is similar to the one shown in Figure 1. Pay attention to the red circles, which demonstrate the success of key pair generation.

Figure 1 Key Pair Creation

2. Export your public key and paste it into your assignment document. You must use two screen-shots to show that you have successfully completed this task. One screen-shot is to show the use of gpg command and the other is to show the exported public key. For example, the screen-shot in Figure 2, shows a public key, which is exported into the file: CC-pubkey.txt.

Figure 2 Screen-shot of a Public Key

3. Explain the how to import the courses public key from the key-server http://pgp.mit.edu (we have created a public key and stored it at the MIT PGP Public Key Server under the name COIT20262-T1-2016). Include in the assignment document the gpg command line, individual options you used and their meaning. As above, use screenshots of website interactions, with accompanying explanations of the screenshots to explain the steps involved in importing this public key from the key-server http://pgp.mit.edu.

4. Create an ASCII text file to store your full-name, your student number, and your student CQU email address (please do not use any other email address). Then using the course public key, encrypt this text file. The resulting file should also be ASCII armored so that it is readable once decrypted by your lecturer / tutor. Failure to do so will result in loss of marks. Submit the resulting encrypted file along with your assignment solutions document (word document) via the online submission system and following the naming convention given above.

Hints:

Where required be detailed and specific about your actions explaining exactly what you did, and why you did not. Document the exact GPG commands you have used, and provide an explanation of what the command does, including the individual command line options, and/or provide screenshots of any interactions with websites.

Brendan Kidwell's practical guide is not the only one available on the Internet. There are plenty of other documents on the Internet that explain how to use GPG for various functions.

Please make sure you will do this assignment very good,

Make sure you will write every thing mentioned.

Attachment:- ass2 pcap.rar