Tips for Fast Phishing Remediation for Quick Recovery

Phishing is every organization’s nightmare, but it doesn’t have to be something that destroys business productivity for long. Whether it’s a malware attack or loss of network credentials, phishing authors aim to disrupt productivity, harm revenue, and force businesses to pay a ransom or lose data from a breach. Following a few standards, administrators can more quickly remediate the effects of a phishing attack.

The Aftermath of a Phishing Attack

Most people understand the basic concepts of phishing. An attacker pretends to be an email sender from a legitimate company to steal data or install malware. For businesses, the aftermath of a phishing attack can have long-term effects on revenue and customer trust. Advanced persistent threats can stay stealthy in an environment for months before discovery. Not only are monitoring systems critical for businesses, but businesses must also put the proper defense and remediation procedures in place.

Phishing threats result in several compromise situations that can be difficult to remediate. A few threats from phishing include:

Business Email Compromise (BEC): A user –usually a high-privilege user—divulges their email credentials to an attacker. The attacker can then authenticate into the business email account and use it to send additional phishing messages or convince other users to divulge sensitive information.

Spear Phishing: An attacker targets a high-privilege user (e.g., an HR or accounting employee) and sends messages to individuals within the corporation to convince them to install malware or divulge sensitive information. Usually, spear phishing involves only one or two targeted users with extensive privileges on the network environment and data stores.

Account Takeover (ATO): When attackers obtain customer data, they automate the discovery of user accounts with the same username and password across multiple sites. Your application can be used for account takeover automation discovery, or a data breach of user accounts from your system can lead to their account takeover on other sites. When the data breach is linked to your business, ATO can lead to a severe loss of customer trust and brand loyalty.

Advanced Persistent Threats: An advanced persistent threat (APT) remains on the network for months, and sophisticated threats can stay on the network even after administrators think they have removed a threat. APTs open backdoors or stay stealthy on the network as they exfiltrate data or allow outsiders to control business devices remotely.

Ransomware: One of the costliest threats is ransomware. Ransomware encrypts all business data in exchange for a large payment to attackers. If businesses use backups to restore data, attackers blackmail them to pay the ransom, or they will expose sensitive data to the public. Business ransomware payments can often be six or seven figures, so implementing anti-phishing software is an expensive lesson.

Social Engineering: Groups of attackers combine phishing with social engineering, usually for larger payouts and more sophisticated attacks. An attacker might send a phishing email asking for payment of a fraudulent invoice and follow up with a social engineering call.

A Checklist for Phishing Remediation

No matter what type of anti-phishing defenses you install on your environment, occasionally, a user might receive a malicious message and fall for the threat. Anti-phishing cybersecurity stops messages from reaching users' inboxes, but no cybersecurity strategy is 100% effective. Cybercriminals continually create new approaches to bypass adequate data protection. Should a phishing threat successfully bypass cybersecurity, administrators must take immediate action against the threat to reduce its environmental damage.

Here are a few procedures to follow to remediate phishing and begin incident response:

Block the Phishing Domain: Malware installed from a phishing attack often “phone home” to a remote domain. The messages sent to the external domain tell the attacker that the environment is open for a compromise, or the malware might send data to an external server. Administrators can block the field on the firewall to interrupt malware communication with the command-and-control (C2) server.

Block the Sender: Although attackers use various spoofing strategies, businesses should set up email cybersecurity to block a sender and the sender’s email server IP address and configure its artificial intelligence analytics to better pick up on new threats. Blocking the sender does not help much after a successful data breach, but recipients must know to block senders when they realize the sender is malicious.

Combine PhishTitan with SpamTitan for a thorough set of email security solutions to stop all malicious emails.

Scan the Environment: Corporate antivirus systems should allow administrators to send global triggers on all devices to scan for malicious software immediately. Sophisticated malware can replicate itself, store a copy of its malicious code on the network, and trick users into executing a payload. Scanning the environment helps administrators quickly find potential vulnerabilities and copies of the malware.

Segment the Network Environment: If the network is segmented, it’s easier to block malware from traversing the environment to various departments. Malware seeks out critical files and targets users with access to critical data. When administrators segment the network into logical parts, the malware is better contained, and only an exploited segment can be cut off from the internet to help reduce damage.

Reset Email Server Passwords: Attackers can access your corporate email accounts for BEC. Administrators must reset everyone’s passwords to block unauthorized access and prevent additional phishing emails from being sent. 

Send Alerts to Affected Individuals: Employees should know that an email server was compromised so administrators can send alerts to affected individuals so that they can stay aware of potential social engineering or additional phishing messages. Users aware of an ongoing attack can stay more alert to stop other threats.

Proactive Anti-Phishing Strategies

Cleaning up your environment after a phishing exploit can take weeks, and administrators can miss a vulnerability and leave malware on the network. The best defense is a proactive offense where your environment has the applications available to stop malware and phishing. Most phishing attacks and payloads can be proactively stopped using email filtering software.

Email filtering software blocks most attacks, but cybersecurity defenses with artificial intelligence are even better. Anti-phishing security like PhishTitan uses artificial intelligence and threat intelligence to stop current threats and block the latest evolution of phishing that attackers deploy daily. A cloud-based email filtering solution like PhishTitan for Microsoft 365 also continually updates with the latest IP addresses, malicious email servers, and threat signatures without administrators needing to install any updates. Combine PhishTitan with SpamTitan for a thorough set of email security solutions to stop all malicious emails, including spam, phishing, and messages with malicious attachments.

Security awareness training also has its benefits. A good security awareness training program provides guidance to users and ways for administrators to test employee resiliency to incoming threats. Administrators can send test email messages to users and identify which users clicked a link in the malicious message, opened the email, and deleted the message outright. Users failing to detect test phishing messages can be offered additional training to help them better detect phishing and social engineering. 

The final solution in your suite of email cybersecurity should be web content filters. Web content filters block users from accessing malicious websites. Whether it’s a false negative that bypasses basic email filters or a link a user found on the internet, web content filters block the site from being loaded in the user’s browser. DNS-based email filters block malicious web content during the DNS lookup step in standard web browsing, and the provider continually updates the database of malicious sites to stop zero-day threats.

To learn more about Microsoft Office 365 anti-phishing software, check out PhishTitan and its product features.