Guide to Digital Forensics
Computer forensics or digital forensics is a term in computer science to acquire authorized evidence found in digital media or computers storage. With digital forensic investigation, the investigator can find what happened to the digital media similar to emails, hard disk, logs, computer system, and the network itself. In lots of case, forensic investigation can produce how the crime could happened and how we can protect ourselves towards it next time.
Some the reason why we have to conduct a forensic investigation: 1. To gather evidences so that it can be used in courtroom to unravel legal cases. 2. To analyze our network strength, and to fill the safety hole with patches and fixes. 3. To get well deleted information or any files within the occasion of hardware or software failure
In computer forensics, the most important things that need to be remembered when conducting the investigation are:
1. The unique proof must not be altered in in any case, and to do conduct the method, forensic investigator must make a bit-stream image. Bit-stream image is a little by little copy of the unique storage medium and exact copy of the original media. The distinction between a bit-stream image and normal copy of the unique storage is bit-stream image is the slack house in the storage. You will not discover any slack house information on a replica media.
2. All forensic processes must observe the legal legal guidelines in corresponding nation the place the crimes happened. Each country has different law suit in IT field. Some take IT rules very severely, for example: United Kingdom, Australia.
3. All forensic processes can solely be performed after the investigator has the search warrant.
Forensic investigators would normally looking on the timeline of how the crimes occurred in timely manner. With that, we will produce the crime scene about how, when, what and why crimes might happened. In a giant firm, it’s suggested to create a Digital Forensic Crew or First Responder Staff, in order that the company may nonetheless protect the evidence until the forensic investigator come to the crime scene.
First Response rules are: 1. On no account should anybody, aside from Forensic Analyst, to make any makes an attempt to recuperate info from any computer system or system that holds digital information. 2. Any attempt to retrieve the information by person said in number 1, needs to be prevented as it may compromise the integrity of the proof, by which turned inadmissible in authorized court.
Primarily based on that rules, it has already explained the necessary roles of having a First Responder Crew in a company. The unqualified individual can solely secure the perimeter in order that nobody can touch the crime scene till Forensic Analyst has come (This can be accomplished by taking picture of the crime scene. They’ll also make notes concerning the scene and who had been present at that time.
Steps need to be taken when a digital crimes happenred in a professional method: 1. Secure the crime scene till the forensic analyst arrive.
2. Forensic Analyst should request for the search warrant from native authorities or firm’s management.
3. Forensic Analyst make take an image of the crime scene in case of if there isn’t a any photos has been taken.
4. If the computer continues to be powered on, don’t turned off the computer. Instead, vancouver used a forensic tools comparable to Helix to get some info that may solely be discovered when the computer is still powered on, comparable to information on RAM, and registries. Such instruments has it’s particular perform as to not write something back to the system so the integrity keep intake.
5. As soon as all live proof is collected, Forensic Analyst cant turned off the computer and take harddisk back to forensic lab.
6. All the evidences have to be documented, in which chain of custody is used. Chain of Custody keep information on the evidence, resembling: who has the evidence for the last time.
7. Securing the evidence should be accompanied by authorized officer reminiscent of police as a formality.
8. Back in the lab, Forensic Analyst take the proof to create bit-stream image, as unique proof should not be used. Normally, Forensic Analyst will create 2-5 bit-stream image in case 1 image is corrupted. After all Chain of Custody still used in this situation to maintain records of the evidence.
9. Hash of the unique evidence and bit-stream image is created. This acts as a proof that unique evidence and the bit-stream image is the exact copy. So any alteration on the bit image will end in different hash, which makes the evidences found develop into inadmissible in court.
10. Forensic Analyst starts to seek out proof within the bit-stream image by rigorously trying at the corresponding location will depend on what sort of crime has happened. For instance: Temporary Internet Recordsdata, Slack Space, Deleted File, Steganography files.