Computer forensics or digital forensics is a term in computer science to acquire authorized proof found in digital media or computers storage. With digital forensic investigation, the investigator can find what happened to the digital media reminiscent of emails, hard disk, logs, computer system, and the network itself. In many case, forensic investigation can produce how the crime could occurred and how we are able to protect ourselves against it subsequent time.
Some the reason why we need to conduct a forensic investigation: 1. To collect evidences in order that it can be used in courtroom to unravel legal cases. 2. To research our network energy, and to fill the security 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, a very powerful issues that need to be remembered when conducting the investigation are:
1. The unique evidence must not be altered in anyways, and to do conduct the process, forensic investigator must make a bit-stream image. Bit-stream image is a bit by bit copy of the unique storage medium and precise copy of the original media. The distinction between a bit-stream image and regular copy of the original storage is bit-stream image is the slack area in the storage. You’ll not find any slack space info on a duplicate media.
2. All forensic processes must follow the legal laws in corresponding nation where the crimes happened. Every country has different regulation suit in IT field. Some take IT rules very seriously, manitoba for instance: United Kingdom, Australia.
3. All forensic processes can solely be performed after the investigator has the search warrant.
Forensic investigators would normally wanting 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 may happened. In a big company, it is recommended to create a Digital Forensic Crew or First Responder Team, so that the corporate may nonetheless protect the evidence till the forensic investigator come to the crime scene.
First Response guidelines are: 1. In no way ought to anyone, aside from Forensic Analyst, to make any makes an attempt to get well info from any computer system or device that holds electronic information. 2. Any try and retrieve the info by person said in number 1, needs to be prevented as it may compromise the integrity of the evidence, by which grew to become inadmissible in legal court.
Based mostly on that guidelines, it has already defined the necessary roles of getting a First Responder Workforce in a company. The unqualified person can solely secure the perimeter so that no one can contact the crime scene until Forensic Analyst has come (This can be accomplished by taking picture of the crime scene. They’ll additionally make notes in regards to the scene and who had been present at that time.
Steps should be taken when a digital crimes occurred in a professional means: 1. Safe the crime scene until the forensic analyst arrive.
2. Forensic Analyst should request for the search warrant from local authorities or firm’s management.
3. Forensic Analyst make take a picture of the crime scene in case of if there is no such thing as a any photos has been taken.
4. If the computer continues to be powered on, don’t turned off the computer. Instead, used a forensic instruments resembling Helix to get some data that may only be found when the computer continues to be powered on, corresponding to information on RAM, and registries. Such tools has it’s particular function as not to write something back to the system so the integrity keep intake.
5. Once all live proof is collected, Forensic Analyst cant turned off the computer and take harddisk back to forensic lab.
6. All the evidences should be documented, in which chain of custody is used. Chain of Custody preserve data on the evidence, equivalent to: who has the evidence for the last time.
7. Securing the evidence should be accompanied by legal officer similar to police as a formality.
8. Back within the lab, Forensic Analyst take the evidence to create bit-stream image, as original evidence should not be used. Usually, Forensic Analyst will create 2-5 bit-stream image in case 1 image is corrupted. Of course Chain of Custody still used on this state of affairs to maintain records of the evidence.
9. Hash of the unique proof and bit-stream image is created. This acts as a proof that authentic evidence and the bit-stream image is the precise copy. So any alteration on the bit image will end in different hash, which makes the evidences discovered grow to be inadmissible in court.
10. Forensic Analyst starts to seek out evidence in the bit-stream image by rigorously trying at the corresponding location depends on what kind of crime has happened. For instance: Non permanent Internet Information, Slack House, Deleted File, Steganography files.