LOGIC BOMBS: Explained
A logic bomb is a type of malicious code embedded in software by a malicious insider or external threat actor that remains dormant until triggered. Unlike conventional malware, a logic bomb doesn’t actively propagate but lies in wait and watches out for certain pre-defined conditions.
Logic bombs are a type of cyber security attack that can hit when they’re least expected and bring an organization’s system to a screeching halt, causing huge financial losses and irreparable damage to an organization’s data bank, network, or infrastructure.
Logic bombs can be implanted by external threats or insiders, like disgruntled employees.
How logic bombs work
When these predetermined conditions are met, the code is triggered and executes one or a series of destructive actions, such as deleting files or disrupting the operation of the network or critical systems.
The triggers can be anything from a specific event, time, or date, which, when executed, cause the logic bomb to execute and offload its destructive payload to the system or data bank.
A logic bomb can carry a computer worm or computer virus. Worms, unlike viruses, don’t need human action to propagate and self-replicate while inside a network.
Their subtle nature can make them extremely dangerous since they can lie dormant and hidden until triggered. They can also have the ability to self-destruct after working, thus destroying evidence of their existence and making it almost impossible to retrace their origins and thwart potential future occurrences.
Types of triggers for logic bombs
Understanding triggers for logic bombs can help thwart or at least mitigate the effects of logic bombs.
- User actions: specific actions like keystrokes or clicking on certain buttons can be a trigger for a logic bomb.
- Time and Date: They can be set to activate on certain dates or times — maybe when they’re less likely to be noticed and thwarted or when they would cause maximum damage.
- Events: the occurrence of particular events, like opening particular files or the execution of certain programs, can trigger a logic bomb.
- System conditions: Conditions like storage capacity thresholds and such can also be triggers.
Time Bomb vs. Logic Bomb
They can sometimes be erroneously used synonymously, but time bombs and logic bombs are types of cyber threats that have different activation methods and characteristics.
While a time bomb is only triggered after the passage of a predetermined amount of time and remains dormant until then, a logic bomb remains dormant until a certain event or condition activates it.
Time bombs rely solely on time conditions, unlike logic bombs, which can have a variety of triggers, including time.
Time bombs can be used on certain important dates, like anniversaries, launches, and other significant events. Their primary purpose is to cause disruptions and damage to systems at specific times or dates, whereas logic bombs often do more, including stealing and corrupting data or sensitive information.
Types of logic bombs
- Event-driven logic bombs: they activate when certain events occur, such as accessing certain files.
- Condition-based logic bombs: they activate when a certain condition is met, e.g., if a certain process is running.
- Time-based logic bombs: they remain dormant until a certain date or time arrives, after which they activate.
- User-activated logic bombs: they rely on specific user actions and inputs to activate, such as keystrokes or button clicks.
Real logic bombs
Stuxnet
Stuxnet, discovered in 2010, targeted Iran’s nuclear program and propagated via removable drives.
SQL Slammer
The SQL Slammer worm exploited vulnerabilities in Microsoft SQL Server in 2003. It spread rapidly, clogged network connections with massive traffic and caused massive disruptions to corporate networks.
Duronio’s Logic Bombs
Orchestrated by Roger Duroni, a former UBS Paine Webber systems employee in March 2002, it targeted critical UNIX servers causing massive disruptions and financial losses amounting to millions.
Consequences of Logic Bombs
System disruption and data loss: they can corrupt and delete crucial files and data, potentially leading to severe productivity and financial losses. They can also be used as a front to steal critical information by disabling security measures or taking advantage of system downtime to infiltrate data banks.
Operational downtime: to prevent further damage and losses, logic bombs can force tech administrators to temporarily shut down their systems. This forced downtime can affect critical services and operations and would be catastrophic for heavy systems-reliant entities like banks.
Financial losses: Related to downtime, operations grinding to a halt during a temporary shutdown can result in heavy financial losses in terms of lost productivity and revenue, recovery losses, and even legal liabilities from clients, data protection, and cyber security regulatory authorities. This can be in addition to causing reputational damage to the victim organization. Clients and partners might lose trust in the organization’s cyber security and data protection capabilities.
Safety and security risks: when aimed at critical infrastructure like banking, power grids, or transportation systems, they can result in huge security risks or even physical injury.
How to prevent logic bombs
Regular Access Reviews: conducting regular reviews of who has access to critical systems and levels of access privileges. This includes deactivating former employees, employees transferred to other departments, auditors, and contractors.
Policies like just-in-time access models ensure that no user has infinite access to systems, which helps limit unauthorized access and minimizes the risk of insider threats. Other helpful policies include end-point security systems to spot and thwart malware and viruses.
Regular Security Assessments: proactively conducting regular security assessment programs like penetration testing and vulnerability scanning to identify potential loopholes and weaknesses in the organization’s infrastructure.
Principle of Least Privilege. The principle of least privilege (PoLP) is an information security concept that maintains that a user or entity should only have access to the specific data, resources, and applications needed to complete a required task or their specific job role and nothing more.
Such restrictions minimize the attack surface as well as the potential impact of an attack.
Monitoring user behaviour: actively monitoring user actions for anomalies, suspicious patterns, or unauthorized access attempts to identify potential insider threats. Auditing and logging of system and user activities can also help detect suspicious behaviour.
Employee training: sensitization and awareness of the potential dangers of logic bombs and common attack pathways such as social engineering, which is one of the most popular ways of implanting logic bombs
Multi-factor authentication: Multi-factor authentication can help prevent unauthorized data access even when one employee’s or user’s credentials have been compromised.
