What to Do If an Employee Clicks a Phishing Link: A Business Incident Response Guide

An employee clicks a link in an email and immediately realizes something does not look right. Maybe the page asked for a Microsoft 365 password, requested multi-factor authentication, downloaded an unexpected file, or simply disappeared after the click.

For a business, what happens in the next few minutes can be critical.

Clicking a phishing link does not automatically mean the company's systems have been compromised. However, the incident should not be ignored. Depending on what happened after the click, an attacker may have obtained login credentials, captured an authentication session, delivered malware, or gained information that could be used in a larger attack.

The employee's first reaction is also important. Employees sometimes close the browser and continue working because they are embarrassed or afraid they will get in trouble. That delay can make an otherwise manageable security incident much more difficult to investigate.

During Cybersecurity Awareness Month, businesses should make one message especially clear to their teams: report suspected phishing incidents immediately. Fast reporting gives IT or the organization's cybersecurity provider an opportunity to investigate the account, device, and related activity before an attacker can move further into the business environment.

This guide explains what a business should do after an employee clicks a phishing link, what IT should investigate, when passwords and sessions need to be secured, and how organizations can prepare employees to respond quickly when phishing gets past the inbox.

 

 

 

 

 

 

What Should an Employee Do Immediately After Clicking a Phishing Link?

The first priority is to report the incident immediately. Employees should not wait for suspicious activity to appear before contacting IT. The sooner the incident is reported, the sooner the business can determine what information may have been exposed and whether additional containment steps are necessary.

What the employee should do next depends on what happened after clicking the link.

If the Employee Only Opened the Link

If the employee clicked the link but did not enter credentials, approve an authentication request, download a file, or provide sensitive information, the risk may be lower—but the incident should still be reported.

IT should review the destination, the employee's device, and relevant security alerts to determine whether the website attempted to deliver malicious content or perform other suspicious activity.

If the Employee Entered a Password

If credentials were entered into a suspected phishing page, the account should be treated as potentially compromised. The employee should immediately notify IT so the password can be changed through a trusted system and the account can be investigated.

Changing the password may not be enough by itself. IT should also review active sessions, recent sign-ins, authentication methods, account recovery information, and other security settings for unauthorized changes.

If the Employee Approved an MFA Request

An unexpected multi-factor authentication request can indicate that an attacker is actively attempting to use stolen credentials. If the employee approved one, IT should investigate immediately and determine whether the attacker successfully authenticated.

This type of attack is closely related to MFA fatigue, where attackers combine compromised credentials with repeated authentication requests or social engineering to convince a user to approve access.

If a File Was Downloaded or Opened

If the phishing page downloaded a file—or the employee opened an attachment associated with the message—the device may require immediate investigation. Employees should avoid deleting evidence or attempting to troubleshoot the situation themselves unless instructed by IT.

Businesses without a dedicated internal security team can use professional cybersecurity solutions to strengthen threat detection, account protection, employee security awareness, and response to suspicious activity.

What Should IT Check After a Phishing Incident?

Once the incident has been reported, IT should determine exactly what happened rather than assuming that changing a password has resolved the problem. The investigation should consider the employee's account, device, email activity, authentication history, and any business systems that may have been accessed.

The scope of the response will depend on whether the employee simply visited a suspicious page or actually entered credentials, approved authentication, downloaded a file, or provided sensitive business information.

Review Sign-In and Authentication Activity

IT should examine recent login activity for unfamiliar locations, devices, IP addresses, applications, or unusual authentication attempts. Activity immediately before and after the phishing incident can help determine whether stolen credentials were actually used.

Repeated MFA requests should also be investigated. As discussed in our guide to MFA fatigue attacks, an unexpected authentication prompt may indicate that an attacker already has the employee's password and is attempting to complete the login.

Revoke Active Sessions

If credentials may have been compromised, changing the password is an important step, but existing authenticated sessions may also need to be revoked. Otherwise, an attacker who already established a valid session could potentially retain access even after the employee changes the password.

Check the Email Account for Unauthorized Changes

Compromised email accounts deserve particular attention. IT should review forwarding rules, mailbox permissions, recovery information, authentication methods, and other settings that an attacker could modify to maintain access or monitor communications.

This is especially important because compromised business email accounts can later be used for impersonation, fraudulent payment requests, or business email compromise (BEC) attacks against employees, customers, and vendors.

Inspect the Employee's Device

If a file was downloaded, an attachment was opened, or suspicious software may have executed, the endpoint should be examined for malicious activity. Depending on the circumstances, IT may need to isolate the device from business resources while the investigation takes place.

Endpoint protection, monitoring, email security, access controls, and network security should work together as part of a broader business cybersecurity strategy.

Determine What Business Data Was Accessible

Finally, the investigation should establish what the affected account could access. A compromised identity may provide access to email, cloud storage, shared documents, customer information, financial systems, or other business applications.

Understanding that access helps the organization determine the potential scope of the incident and whether additional accounts, systems, customers, vendors, or business partners need to be investigated.

How Can a Business Contain a Phishing Incident?

Once IT has identified the likely scope of the phishing incident, the next priority is containment. The objective is to prevent the attacker from continuing to use compromised credentials, spreading the attack to other employees, or accessing additional business systems.

Secure Compromised Accounts

Accounts that may have been exposed should be secured immediately. This can include changing passwords from a trusted device, revoking active sessions, reviewing authentication methods, and removing unauthorized changes made to the account.

If the employee reused the compromised password on other business applications, those accounts should also be reviewed and secured.

Isolate Affected Devices When Necessary

If there is evidence that malware was downloaded or executed, IT may need to isolate the affected computer from the business network while it is investigated. This can help prevent malicious software from communicating with external systems or attempting to reach other devices and resources.

The device should be examined using the organization's established security and incident-response procedures rather than immediately wiping it and potentially destroying useful evidence.

Search for the Same Phishing Message Across the Organization

A phishing email sent to one employee may have been delivered to many others. IT should determine whether additional employees received the same or similar message and, where possible, remove malicious messages from company mailboxes before more users interact with them.

Employees can also be alerted to the campaign so they know what to watch for without unnecessarily circulating the malicious link or attachment.

Protect Customers, Vendors, and Other Employees

If an attacker gained access to a legitimate business mailbox, the incident may extend beyond the original employee. Attackers can use trusted accounts to send convincing requests to coworkers, customers, vendors, or financial personnel.

This can develop into a business email compromise incident involving fraudulent invoices, payment changes, sensitive information, or additional credential theft. Prime Tech Business has previously covered how organizations can protect against Business Email Compromise scams.

Document What Happened

The business should document when the phishing email was received, when the employee interacted with it, what information was entered, which actions IT performed, and what suspicious activity was discovered.

This information can help with the technical investigation and provide valuable context when improving security controls after the incident.

Organizations without sufficient internal IT resources can also use managed IT services to help maintain security controls, monitor business technology, and respond when suspicious activity occurs.

How Can Businesses Prevent the Next Phishing Incident?

After the immediate threat has been contained, the incident should become an opportunity to improve the organization's security. The goal is not simply to tell the employee to be more careful. Businesses should determine why the phishing attempt reached the employee, what allowed it to become convincing, and which additional security controls could reduce the impact of a similar attack.

Strengthen Email Security

Email filtering and threat protection can help identify malicious links, suspicious attachments, impersonation attempts, and other common phishing techniques before they reach an employee's inbox.

No email security system will stop every malicious message, however. Email protection should therefore operate as one layer within a broader cybersecurity strategy.

Use Strong Multi-Factor Authentication

MFA can prevent a stolen password from immediately becoming a compromised account, but the authentication method and configuration matter. Businesses should evaluate whether their current MFA implementation provides sufficient resistance to phishing and social engineering.

Employees should also understand that an unexpected MFA request can itself be a warning sign. If an authentication notification appears when the employee is not signing in, it should be denied and reported rather than treated as a routine interruption.

Provide Practical Employee Security Awareness Training

Cybersecurity awareness training should prepare employees for situations they may actually encounter: fake Microsoft 365 login pages, urgent payment requests, impersonated executives, fraudulent password-reset messages, malicious attachments, and unexpected MFA prompts.

Just as importantly, employees should know how to report a suspicious message and what to do immediately if they make a mistake. A culture of fast reporting can significantly improve the organization's ability to respond.

Limit the Damage a Compromised Account Can Cause

Businesses should also review user permissions and access to sensitive systems. Employees should have access to the information and applications required for their roles without automatically receiving unnecessary privileges across the organization.

This principle can reduce the potential impact if one employee account is compromised.

Monitor Accounts, Devices, and Business Systems

Security monitoring can help identify suspicious sign-ins, unusual account behavior, endpoint threats, and other indicators that may appear after a successful phishing attack.

For small and midsize organizations without a dedicated internal IT department, managed IT services can provide ongoing monitoring, technology management, cybersecurity support, and assistance responding to incidents.

Respond to Phishing Before It Becomes a Larger Security Incident

An employee clicking a phishing link does not automatically mean a business has suffered a major breach. What matters is what happened after the click—and how quickly the organization responds.

If credentials were entered, an MFA request was approved, a malicious file was opened, or sensitive information was provided, the incident should be investigated immediately. Securing the affected account is important, but businesses should also review authentication activity, active sessions, endpoint security, mailbox changes, and access to other company systems.

Most importantly, employees should feel comfortable reporting mistakes quickly. Hiding or delaying a phishing incident gives an attacker more time to use stolen credentials, access company information, impersonate trusted employees, or expand the attack.

During Cybersecurity Awareness Month, businesses can use this opportunity to review not only whether employees can recognize phishing, but whether the organization is prepared to respond when someone eventually clicks.