'Cyber causes' extension
Extension of the Industrial or Technical Risks module that opens the malicious-origin angle in a hazard study.
Activation
Methods tab of the study context, Extensions section. A single switch governs every addition.
What the extension does not change
Cyber causes do not carry a PIGC probability class: the probability of the hazard study is still calculated from accidental causes only. The extension adds a reading, it does not alter the existing SEVESO/ICPE regulatory rating.
What it opens up
In the PHA — Hazard study
Entry of malicious-origin causes on initiating events. An initiating event can thus carry both accidental causes (rated by PIGC) and cyber causes (rated elsewhere).
A Vp double-counting check flags inconsistencies with Cyber-LOPA.
In the fault tree
Linking of tree leaves to plant components, then grafting of cyber compromises onto the leaves carried by a given component.
| Element of a graft | Content |
|---|---|
| Component | Plant asset concerned |
| ATT&CK for ICS technique | Attack technique from the MITRE framework |
| Role, Label | Description of the compromise |
| Probability | Probability of the compromise |
The cyber view is derived
Checking Cyber view displays the tree enriched with compromises, in read-only mode: the saved tree is never modified. Uncheck it to return to editing the original tree.
Mixed minimal cut sets
Cut sets calculated on the enriched tree carry a nature: Accidental, Mixed or Pure cyber.
A "common cause" flag appears when the same technique reaches both the function and its protection: the barriers are then no longer independent, which invalidates the base assumption of the probabilistic calculation.
Calculated Vp
The enriched tree produces a Vp: the probability of the feared event given that the attacker controls the grafted assets. This is the value that feeds the decomposed rating of the IEC 62443 module.
Overview
The Safety ↔ Security page consolidates the whole chain and flags inconsistencies between modules.