Table of Contents
September 27, 2024
|13m
Secrets of Prioritizing Incidents
Whenever an alert or incident is reported to security operations or incident response teams, the first task of a security analyst or incident responder is to assess the alert and prioritize it. False assessment and poor prioritization can lead to massive disruptions. Imagine seeing a flood of alerts and incidents before you—it's in these moments that prioritization becomes critical. Without a well-defined prioritization strategy, you're likely to fail in addressing the most important threats. On the other hand, a good prioritization plan can save organizations from catastrophe, ensuring that the most serious risks are dealt with promptly and effectively.
Could you please prioritize these incidents?
Ransomware attack on critical customer database
Phishing attack compromises CEO’s email
DDoS attack on company website during product launch
Unauthorized login attempt blocked by firewall
Malware infection localized to single employee workstation
Upon reading this article, you will gain the knowledge to prioritize these incidents in a strategic way.
In this article, we'll unlock the secrets of incident prioritization for security analysts and incident responders. We'll dive into the most critical methodologies used for assessing and prioritizing incidents, based on three main factors- functional impact, information impact, and recoverability effort. We'll also explore best practices and real-world examples of how to streamline the response process.
Why Prioritizing Incidents is Crucial
Every organization, from small startups to large enterprises, is vulnerable to a range of cybersecurity incidents. The challenge is deciding which incidents to address first when they all demand immediate attention. Not every alert or suspicious activity carries the same risk, but missing a high-priority incident could result in severe consequences. That's why effective incident prioritization is necessary—it helps optimize the allocation of resources, ensuring that critical threats are handled before they can do significant damage.
Many organizations experience hundreds or even thousands of security alerts daily. Incident handlers must evaluate, classify, and prioritize each one, categorizing it as benign, suspicious, or malicious. Once classified, incidents must be further ranked based on their potential impact to the business. Let's explore the various methods of categorizing and prioritizing incidents.
Functional Impact: The First Layer of Prioritization
The first step in prioritizing incidents is evaluating their functional impact on the organization. This method focuses on how the incident affects the company's daily operations. Depending on the industry, an incident affecting one critical service can have devastating consequences, while another may be manageable with minimal disruption.
Functional Impact Categories
High Impact: The organization is unable to provide one or more critical services to all its users. For instance, an attack that compromises a payment system for an e-commerce site would halt revenue streams, making it a top priority.
Medium Impact: The organization loses the ability to offer a critical service to some users. For example, a software outage may affect a small subset of customers or a less essential part of the business.
Low Impact: The organization can still provide all critical services, but efficiency is reduced. This may include slow performance or degraded user experience, which while inconvenient, does not threaten the company's core operations.
No Impact: There is no measurable effect on the organization's ability to conduct its regular business.
By understanding how an incident impacts the business, analysts can prioritize incidents that directly threaten the company's ability to operate. This approach is a key part of an effective Cyber Incident Response Plan.
|
Scenario
|
High Impact
|
Medium Impact
|
Low Impact
|
None Impact
|
|
Ransomware attack encrypts entire company's data
|
High: Revenue loss; critical business function down.
|
|||
|
Website outage during a major product launch
|
Medium: Affects a subset of users, but core operations continue.
|
|||
|
E-commerce site unable to process credit card transactions
|
Low: Minor productivity loss for internal teams.
|
|||
|
DDoS attack on customer-facing website
|
Low: Non-critical service; affects a small team.
|
|||
|
SQL injection attack on an internal database
|
High: Affects all users, causes financial and reputational damage.
|
|||
|
Phishing attack compromises one executive's email
|
Medium: Affects specific departments, but core services remain intact.
|
|||
|
Malware infection on 10 employee workstations
|
Low: Affects marketing efforts, but no direct impact on revenue.
|
|||
|
Customer support portal down for a small geographic region
|
Low: Routine maintenance; minimal impact on business operations.
|
|||
|
Exploitation of vulnerability in a non-critical service
|
Low: Temporary communication disruption, no effect on external services.
|
|||
|
Partial outage of internal file-sharing system
|
None: No effect on operations.
|
|||
|
Credential theft of a single low-level employee
|
High: Business operations halted; critical data inaccessible.
|
|||
|
Loss of marketing automation tools for campaign
|
High: Website unavailable, causing revenue loss and service disruptions.
|
|||
|
Internal email service slow, but still operational
|
High: Potential exposure of sensitive business and financial information.
|
|||
|
Temporary loss of access to HR portal
|
Medium: Affects productivity, but core systems and data unaffected.
|
|||
|
Unauthorized login attempt detected but blocked
|
Medium: Could lead to lateral movement within the network.
|
|||
|
Temporary issue with internal employee chat system
|
Medium: Affects a subset of users, but business operations continue.
|
|||
|
Routine patch deployment causes temporary slowdowns
|
Low: Data integrity could be at risk, but no immediate disruption.
|
|||
|
Adware detected on an employee's device
|
Low: Non-critical impact; productivity affected slightly.
|
|||
|
Reconnaissance scan from an external IP
|
Low: No compromise, but needs further investigation.
|
|||
|
Non-business-critical system logs minor errors
|
None: No direct impact on services or data.
|
Information Impact: Assessing Data Breaches and Confidentiality
When classifying incidents, analysts must also consider the information impact—the degree to which the incident affects the confidentiality, integrity, and availability of the organization's data. For industries that manage sensitive data, such as healthcare or finance, information impact can often outweigh functional impact.
Types of Information Impact
Integrity Loss: Sensitive or proprietary information is altered or deleted. For example, an attack on a database that results in corrupted customer records would compromise data integrity.
Proprietary Breach: Proprietary or confidential information is accessed or exfiltrated. Imagine if a hacker managed to download a secret recipe from a food manufacturer; this breach could have irreversible consequences.
Privacy Breach: Personally identifiable information (PII), such as Social Security numbers, names, or addresses, is accessed without authorization. While this may not immediately affect operations, it can lead to legal repercussions and a loss of customer trust.
No Impact: The incident does not compromise any information. Even though a system might be attacked, the data could remain encrypted or otherwise protected, rendering the breach ineffective.
Organizations that prioritize based on information impact are particularly concerned with maintaining the integrity and confidentiality of their data. This becomes crucial in industries where trust is paramount, such as financial services and healthcare. Understanding these impacts is a key part of implementing an effective Cyber Incident Response Plan.
|
Scenario
|
High Impact
|
Medium Impact
|
Low Impact
|
None Impact
|
|
1. Data breach exposing customer Social Security numbers
|
High: Personal data exposed; high risk of identity theft.
|
|||
|
2. Database breach leaking proprietary formulas
|
High: Proprietary intellectual property stolen.
|
|||
|
3. Phishing attack leading to CEO email compromise
|
High: Sensitive business communications exposed.
|
|||
|
4. Compromise of cloud storage with unencrypted client data
|
High: Client data accessible by unauthorized parties.
|
|||
|
5. Data breach exposing financial information of customers
|
High: Credit card numbers, banking info compromised.
|
|||
|
6. Exfiltration of source code from software development team
|
High: Proprietary software code stolen, leading to potential cloning.
|
|||
|
7. Attack on encrypted database, but no decryption
|
Medium: Attackers gained access, but encryption remains intact.
|
|||
|
8. Theft of login credentials for non-admin employees
|
Medium: Non-privileged accounts accessed, potential lateral movement.
|
|||
|
9. Compromise of internal documents (no sensitive data)
|
Medium: Internal but non-sensitive business information stolen.
|
|||
|
10. Misconfiguration of public cloud storage exposes files
|
Medium: Limited impact; non-sensitive files visible externally.
|
|||
|
11. SQL injection attack alters non-critical public data
|
Low: Public-facing data compromised but easily corrected.
|
|||
|
12. Unauthorized login attempt blocked at the firewall
|
Low: No data accessed or compromised, but investigation required.
|
|||
|
13. Adware infection on an employee computer
|
Low: No sensitive data compromised; minor annoyance to productivity.
|
|||
|
14. Spear phishing attempt targeting HR but blocked
|
Low: No data compromised, email flagged and blocked.
|
|||
|
15. Malware detected and quarantined before spreading
|
Low: No data exfiltrated, early detection of malware.
|
|||
|
16. Unauthorized access to encrypted sensitive data, no decryption
|
None: Data encrypted and unreadable by attackers.
|
|||
|
17. Firewall detects and blocks port scanning from external source
|
None: No access to data, only reconnaissance attempt.
|
|||
|
18. Temporary exposure of marketing materials on public cloud
|
None: Non-sensitive material exposed, no real impact.
|
|||
|
19. Reconnaissance activity detected, no further action
|
None: No data accessed, merely reconnaissance attempt logged.
|
|||
|
20. Phishing email detected but not opened by employees
|
None: Email flagged, no data compromised.
|
|||
Recoverability Effort: Understanding the Scope and Scale of Recovery
The next layer of prioritization focuses on the recoverability effort—how difficult and time-consuming it will be to recover from the incident. According to the NIST Special Publication 800-61, organizations categorize recovery into four levels:
Not Recoverable: The incident is irreversible. For instance, if sensitive data is leaked online, there is no way to retrieve or prevent others from accessing it.
Extended: Recovery is unpredictable and could take a significant amount of time. This is often the case with large-scale breaches that affect critical systems or require outside assistance.
Supplemented: Recovery is somewhat predictable but requires additional resources such as more staff or hardware.
Regular: Recovery is straightforward and predictable. For example, cleaning up a malware infection on an individual workstation can often be handled internally with existing resources.
By evaluating the recoverability effort, incident responders can better prioritize incidents based on the resources required to restore normal operations. Incidents that are deemed unrecoverable or require extensive time and effort to resolve are often escalated in priority.
|
Scenario
|
Not Recoverable
|
Extended
|
Supplemented
|
Regular
|
|
1. Intellectual property (IP) theft and leaked online
|
Not Recoverable: IP has been made public; no way to reverse exposure.
|
|||
|
2. Ransomware attack where backup data is also encrypted
|
Not Recoverable: No viable backups and all critical data is lost.
|
|||
|
3. DDoS attack causing prolonged website downtime
|
Extended: Requires third-party support and possibly hardware upgrades.
|
|||
|
4. Malware spread through multiple critical systems
|
Extended: Requires system-wide reimaging and possibly third-party forensic support.
|
|||
|
5. Major breach of sensitive customer data
|
Extended: Legal, PR, and external investigation required; lengthy resolution process.
|
|||
|
6. Critical server failure due to cyber attack
|
Extended: Hardware replacement and complex recovery procedures needed.
|
|||
|
7. Compromise of internal systems, but with partial backups
|
Supplemented: Recovery requires partial backups and additional IT staff.
|
|||
|
8. Credential theft of high-level administrator accounts
|
Supplemented: Recovery involves resetting admin credentials and additional monitoring tools.
|
|||
|
9. Exfiltration of source code, but not widely distributed
|
Supplemented: Requires patching security gaps and hiring additional security experts.
|
|||
|
10. Malware infection on non-critical systems
|
Supplemented: Reimaging systems with additional staffing or external help.
|
|||
|
11. Phishing attack leading to compromise of low-level credentials
|
Supplemented: Need to reset credentials and possibly deploy more robust authentication tools.
|
|||
|
12. Malware detected early, localized to a single workstation
|
Regular: Simple reimaging of the workstation can resolve the issue.
|
|||
|
13. Reconnaissance activity detected, no further intrusion
|
Regular: No data affected, basic monitoring adjustments can resolve.
|
|||
|
14. Unauthorized login attempt blocked by firewall
|
Regular: Incident resolved with minor log review and IP block.
|
|||
|
15. Minor DDoS attack mitigated by existing security measures
|
Regular: Routine response from existing firewall and anti-DDoS systems.
|
|||
|
16. Single machine infected with adware
|
Regular: Simple adware removal tool can resolve.
|
|||
|
17. Non-critical system hit by malware, quick recovery possible
|
Regular: Routine reimaging of the system; no additional resources needed.
|
|||
|
18. Public-facing website defaced
|
Regular: Website can be restored from backup with minimal disruption.
|
|||
|
19. Password reset vulnerability discovered but no breach
|
Regular: Patch and routine password policy update required.
|
|||
|
20. Internal file-sharing system compromised, limited to a single group
|
Regular: Can be quickly restored from backups with minimal resources.
|
Combining Prioritization Factors for a Holistic Approach
Organizations rarely rely on just one method of prioritization. In most cases, functional impact, information impact, and recoverability effort are combined to create a more comprehensive view of the incident's severity. Some organizations even assign a weighted score to each of these factors to calculate an overall priority ranking for each incident.
By combining these factors, incident responders can ensure they are focusing their efforts on the incidents that pose the greatest risk to the organization. This approach is crucial for effective incident response.
Example Scenario
Consider an organization that experiences three different incidents on the same day:
Incident A: A malware infection is detected on a single employee's computer. The functional impact is low, the information impact is none (no data exfiltrated), and the recoverability effort is regular (the machine can be re-imaged). This incident receives a low priority.
Incident B: A distributed denial-of-service (DDoS) attack targets the company's customer-facing website, rendering it unavailable. The functional impact is high (the business cannot process transactions), the information impact is none, and the recoverability effort is extended (IT needs additional resources to restore service). This incident receives a high priority.
Incident C: A phishing attack successfully compromises an employee's credentials, leading to a breach of sensitive financial data. The functional impact is low (the business can continue), but the information impact is high (sensitive data exfiltrated), and the recoverability effort is supplemented (external forensic teams are needed to investigate the breach). This incident also receives a high priority.
|
Scenario
|
Functional Impact
|
Informational Impact
|
Recoverability Effort
|
Overall Priority
|
|
1. Ransomware attack on critical customer database
|
High: Business operations halted, no access to customer data.
|
High: Sensitive customer information (PII) at risk.
|
Extended: Requires significant time and effort to restore data, may need third-party support.
|
High: Immediate action required to mitigate severe operational and data loss.
|
|
2. Phishing attack compromises CEO’s email
|
Medium: Business operations continue, but executive communications compromised.
|
High: Sensitive internal and financial information exposed.
|
Supplemented: Requires expert analysis and additional security protocols to mitigate further risk.
|
High: Critical due to potential data exposure, but business operations are unaffected.
|
|
3. DDoS attack on company website during product launch
|
High: Website down, significant revenue loss during critical period.
|
None: No data accessed or compromised.
|
Extended: Third-party support needed to mitigate ongoing attack.
|
Medium: High functional impact, but no data loss; recovery efforts needed for business continuity.
|
|
4. Unauthorized login attempt blocked by firewall
|
Low: No disruption to services, normal operations.
|
None: No data accessed.
|
Regular: Simple review and adjustment to security settings.
|
Low: Routine issue with no immediate threat or disruption.
|
|
5. Malware infection localized to single employee workstation
|
Low: Minimal effect on business productivity.
|
Low: No sensitive data compromised.
|
Regular: Standard malware removal, no additional resources needed.
|
Low: Low impact on both operations and data, easy to resolve.
|
Conclusion
In today's fast-paced cybersecurity landscape, security analysts and incident responders need to prioritize incidents quickly and efficiently. Focusing on functional impact, information impact, and recoverability effort allows teams to manage incidents with precision, ensuring the most critical threats are addressed first.
By following best practices such as creating incident response playbooks, leveraging automation, and continuously reviewing procedures, organizations can enhance their incident prioritization process, protecting themselves from the most significant cybersecurity threats.
Implementing these strategies ensures that your security team can respond to the growing number of incidents with confidence and clarity, minimizing the risk to the business and maximizing operational resilience.
We hope this article helps you learn about prioritizing incidents. Visit our website, thesecmaster.com, and our social media page on Facebook, LinkedIn, Twitter, Telegram, Tumblr, Medium, and Instagram and subscribe to receive tips like this.
You may also like these articles:
Arun KL
Arun KL is a cybersecurity professional with 15+ years of experience in IT infrastructure, cloud security, vulnerability management, Penetration Testing, security operations, and incident response. He is adept at designing and implementing robust security solutions to safeguard systems and data. Arun holds multiple industry certifications including CCNA, CCNA Security, RHCE, CEH, and AWS Security.
