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[OR] [MIB] [E3] [CBS] [1] [SuPS] Identify Severe but Plausible Scenarios

Written by Moh Heng Goh | Mar 3, 2026 8:40:30 AM

CBS-1 Securities Trading & Execution 

Introduction

In line with operational resilience principles and the concept of “Severe but Plausible Scenarios” as articulated in the BCM Institute methodology, this chapter identifies extreme yet credible disruption events that could materially impact CBS-1 Securities Trading & Execution.

Severe but plausible scenarios are not theoretical extremes; rather, they represent realistic, high-impact disruptions that financial institutions must be able to withstand within defined impact tolerances.

For Maybank Investment Bank, Securities Trading & Execution is a mission-critical service involving client onboarding, trade lifecycle processing, clearing and settlement, custody coordination, margining, reconciliation, regulatory reporting, and system recovery.

The scenarios below integrate operational, cyber, ICT, third-party, and market infrastructure risks to ensure holistic resilience planning, including proactive controls and evidence of preparedness.
 

Table P5: Identify Severe but Plausible Scenarios for CBS-1

Sub-CBS Code

Sub-CBS

Severe but Plausible Scenario

Impact / Effect

Proactive Risk Management Action (Evidence)

Link to Integration of Cyber & ICT Risks

1-1

Client Onboarding for Trading

Core KYC/AML system outage due to ransomware attack

Inability to onboard new clients; regulatory breach risk

Periodic cyber penetration testing; segregated onboarding environment; offline KYC fallback procedures; RTO defined

Cyber attack on customer data systems; ICT resilience for onboarding platforms

1-2

Order Capture & Validation

OMS (Order Management System) failure during peak trading hours

Orders cannot be captured or validated; revenue loss

Active-active OMS architecture; real-time monitoring; manual order-taking protocol; DR drills

ICT system resilience; network redundancy; application failover controls

1-3

Pre-Trade Risk Controls

Risk limit engine malfunction, causing incorrect limit validation

Exposure to unauthorised risk positions

Automated limit reconciliation; daily parameter review; independent risk oversight

Cyber manipulation of risk parameters; data integrity controls

1-4

Trade Execution (Exchange-Traded)

Exchange connectivity disruption or DDoS attack

Inability to execute client trades; market exposure risk

Dual connectivity to exchange; alternative broker routing, market disruption playbooks

DDoS resilience; telecom redundancy; exchange API security

1-5

Trade Execution (OTC / Structured Products)

Counterparty default during volatile market conditions

Financial loss; settlement disputes

Counterparty credit monitoring; CSA agreements; exposure limits; stress testing

ICT systems supporting exposure calculation; secure communication channels

1-6

Algorithmic & Electronic Trading Management

Algorithm malfunction due to corrupted code deployment

Erroneous trades; market abuse risk

Pre-deployment testing; kill-switch controls; real-time trade surveillance; change governance logs

Secure DevOps lifecycle; code integrity controls; privileged access management

1-7

Trade Confirmation & Client Notification

Messaging system outage or email server compromise

Clients not informed of executed trades; dispute risk

Automated confirmation reconciliation; SMS backup channel; secure messaging gateway

Email server security, encryption, business communication platform resilience

1-8

Trade Capture & Booking

Trade capture system database corruption

Inaccurate books and records

Real-time data replication; hourly backup; reconciliation with front-office system

Database integrity monitoring; backup encryption; ICT disaster recovery

1-9

Clearing & Settlement Processing

Central clearing house system failure or payment gridlock

Failed settlements; liquidity stress

Liquidity buffer monitoring; alternate settlement bank; settlement cut-off controls

SWIFT security controls, payment gateway redundancy, and third-party infrastructure resilience

1-10

Custody & Safekeeping Coordination

Custodian bank cyber breach affecting securities records

Client asset integrity concerns; reputational damage

Custodian due diligence; periodic SOC report review; reconciliation frequency increase

Third-party ICT risk management; secure data exchange protocols

1-11

Margin & Collateral Management

Extreme market volatility is causing the margin calculation system overload

Margin shortfall; liquidity strain

Stress testing, automated margin calls, collateral buffer policies

Risk engine scalability; cloud resilience; cyber protection of collateral systems

1-12

Corporate Actions Processing

Failure to process high-volume corporate action due to a system error

Incorrect entitlement allocation

Maker-checker controls; automated CA feeds; reconciliation with custodian

Secure API feeds; ICT monitoring of data feeds; third-party data risk

1-13

Reconciliation & Exception Management

Reconciliation tool failure during the month-end

Undetected breaks; financial misstatement risk

Independent reconciliation platform; escalation matrix; audit trail logs

Data integrity assurance; access control; ICT monitoring

1-14

Regulatory Reporting & Surveillance

Regulatory reporting platform compromised or corrupted

Regulatory breach; fines and penalties

Pre-submission validation checks, dual control approval, and periodic compliance audit

Secure regulatory reporting system; encryption; audit logging; cyber monitoring

1-15

Business Continuity & System Recovery for Trading

Primary data centre outage due to fire or major cyber incident

Full trading disruption

Secondary DR site (geographically separate); annual full failover testing; board-approved BCP

ICT disaster recovery architecture; cyber incident response integration

Integration with Cyber and ICT Risks

Across all Sub-CBS processes, severe but plausible scenarios are closely linked to cyber threats (ransomware, DDoS, insider threats), ICT infrastructure failures (data centre outage, network disruption, database corruption), third-party technology risk (custodians, exchanges, clearing houses), and digital system vulnerabilities (algorithmic trading platforms, regulatory reporting systems).

The integration ensures:

  • Alignment between operational resilience and cyber resilience frameworks
  • Board-level visibility of ICT dependencies
  • Defined Recovery Time Objectives (RTO) and Recovery Point Objectives (RPO)
  • Regular scenario testing and simulation exercises

Identifying severe but plausible scenarios for CBS-1 Securities Trading & Execution enables Maybank Investment Bank to move beyond traditional business continuity planning into a proactive resilience posture.

By stress-testing each stage of the trade lifecycle against credible high-impact events—including cyberattacks, system failures, third-party disruptions, and extreme market volatility—the Bank strengthens its ability to remain within defined impact tolerances.

The integration of cyber and ICT risk considerations into every Sub-CBS ensures that resilience is not siloed but embedded across technology, people, processes, and external dependencies.

This structured scenario identification supports regulatory expectations, enhances client trust, and reinforces Maybank Investment Bank’s commitment to operational resilience in Malaysia’s capital markets ecosystem.

 

Designing a Resilient Investment Banking Model: The Maybank Investment Bank Journey

eBook 3: Starting Your OR Implementation
CBS-1 Securities Trading & Execution
CBS-1 DP CBS-1 MD CBS-1 MPR CBS-1 ITo CBS-1 SuPS  CBS-1 ST  eBook 2
   

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