Insider attacks have always been a matter of serious concern as it violates confidentiality of data. There is a huge rise in severity of Insider attacks such as data theft, fraud, and sabotage by insiders who are trustworthy. These threats are driven by personal motivation and changing work environment. According to a recent survey by cyber security professionals in 2024,the number of organizations that report Insider Attacks increased from 66% to76% from 2019 to 2024.After COVID-19 most of the IT companies switch to work from home mode, which leads to rise in Insider attacks. Detecting Insider Attacks is a complex task as only 16% of the organization claims that they are effective in handling the attacks yet there is still a significant scope for enhancing threat management strategies. The paper provides the incidents of Insider attack and their drastic effect on organization. Also, a comparative analysis of work done by several authors on Log file based technique to detect Insider attacks were discussed which help the further researchers to carry out their research work.