Offshore Oil&Gas operations are a key part of the supply of energy in many countries. Worldwide, about a third of the oil is produced offshore and, in Europe, more than 80% of the current Oil&Gas production takes place offshore. Offshore Oil&Gas installations may be the target of malicious acts aiming at causing severe impacts in terms of damage and media coverage, comparable to the outcomes of major accidents originating from safety-related causes. The attractiveness of such installations is linked to the high amount of hazardous substances handled, their socio-political location, and the possibility of obtaining proprietary information important for the business. In the present study, in order to frame a clear picture of the security threats affecting offshore Oil&Gas operations, a database of 2222 security-related incidents occurred in the last 49 years was developed and analysed. Itemized categories used to classify the events by industrial sector, security threats, attack modes, and final scenarios triggered by the malicious acts, were defined and analysed with Exploratory Data Analysis (EDA). Correlations among itemized categories were investigated using Correspondence Analysis (CA). Overall, the results show the concreteness of the security threats to offshore Oil&Gas installations.