What Is Phishing? Everything You Need to Know

Despite years of awareness training, advanced detection systems, and evolving defense strategies, phishing remains one of the most pervasive cyber risks as attackers refine their tactics to exploit both human trust and security blind spots.  

To help security teams better address evolving phishing scams, we’ll provide a comprehensive look at what phishing is, how attacks operate, emerging trends, and best practices for prevention. 

What Is Phishing in Cybersecurity?  

Phishing is a type of social engineering attack where adversaries impersonate trusted entities to trick victims into revealing sensitive information, installing malware, or granting unauthorized access. According to Verizon’s 2025 Data Breach Investigations Report, social engineering attacks account for nearly a quarter of external security breaches – 57% of those incidents involve phishing.  

Unlike many other types of cyberattacks, phishing targets the human layer. Emails, text messages, phone calls, and even QR codes can serve as delivery mechanisms. These “lures” are crafted to look authentic, mimicking brands, colleagues, or executives, and they typically use urgency or fear to apply pressure. 

How Does Phishing Work?  

Phishing attacks generally unfold in four stages: 

• The lure: Attackers distribute a message posing as a reputable sender.  
• The hook: The message contains a malicious element, like a link or attachment.  
• The interaction: Victims click, download, reply, or otherwise engage with the malicious feature.  
• The exploit: Attackers harvest credentials, install malware, or gain entry to sensitive systems.  

Notably, phishing often acts as the initial access vector for larger campaigns, such as ransomware attacks.  

Phishing Techniques: Types of Attacks  

Cyber attackers leverage a wide variety of tactics to lure in their victims; some of the most common strategies include: 

Spear Phishing 

Spear phishing attacks are highly targeted campaigns crafted for a specific organization or individual. Attackers may research victims via LinkedIn or other public records to ensure the messages include legitimate context.  

Clone Phishing 

In clone phishing attacks, adversaries copy a legitimate message, like an invoice or calendar invite, and replace the links or attachments with malicious ones. Because these “lures” are almost identical to their legitimate counterparts, clone phishing scams are particularly difficult to recognize.  

Whaling 

Focused on senior executives, board members, or other high-value targets, whaling attacks are often designed to trick victims into transferring large sums of money. These lures are typically designed to look like urgent legal or financial matters that require immediate action. 

Bulk Email Phishing 

The most common variety of phishing attack, bulk email phishing relies on mass-distributed messages sent to thousands of addresses at once. These scams anchor on volume and probability rather than strategically crafted lures.  

Business Email Compromise  

Business email compromise (BEC) is a form of spear phishing where attackers impersonate a colleague to manipulate victims into sending money or other valuable data. According to the FBI, BEC scams have cost victims over $55 billion since 2013.  

Smishing  

Also known as SMS phishing, smishing uses text messages to lure victims into engaging. Attackers may impersonate banks, package carriers, government agencies, or other trusted senders.  

Vishing  

Vishing, or voice phishing, is carried out over the phone. Attackers often leverage caller ID spoofing, so the scam calls appear to come from local phone numbers or legitimate organizations.  

Phishing Trends: AI, QR Codes, and Hybrid Attacks  

Attackers are constantly refining their phishing techniques to bypass defenses, overwhelm users, and exploit new technologies. Today, attackers are increasingly leveraging AI-driven campaigns, malicious QR codes, and multi-channel attacks:  

• AI Phishing: It takes scammers about 16 hours to manually craft a convincing phishing email; with the help of AI, attackers can design highly targeted messages in minutes. As more attackers add AI to their toolkit, they’re increasingly adding sophisticated deepfake messages to phishing campaigns. According to FBI Special Agent in Charge, Robert Tripp, “As technology continues to evolve, so do cybercriminals' tactics. Attackers are leveraging AI to craft highly convincing voice or video messages and emails to enable fraud schemes against individuals and businesses alike.”  
• QR Code Phishing (Quishing): QR-based phishing has exploded as organizations and consumers alike have embraced QR codes for everyday convenience. In the first quarter of 2025, cyber attackers distributed emails containing more than 1.7 million malicious QR codes. Attackers may embed malicious QR codes in emails, PDFs, or even physical lures, which redirect victims to credential-harvesting pages or malware downloads. Because QR codes mask the final URL, they evade most filtering tools.  
• Hybrid Attacks: Attackers increasingly orchestrate phishing campaigns that span email, text, phone calls, and even social media to build multi-threaded scams. These hybrid, multi-step approaches are harder to detect with point defenses, highlighting the need for layered security strategies.  

Phishing Attack Examples 

Security leaders understand that phishing is a top cybersecurity risk – 76% say phishing is one of their top concerns. Still, a look at real-world incidents helps clarify the evolving nature of phishing scams.  

Medusa Ransomware Gang Phishing Campaigns  

Since 2021, the RaaS Medusa variant has claimed more than 300 victims across a range of critical infrastructure sectors. According to a joint advisory from the FBI, CISA, and MS-ISAC, Medusa developers often recruit initial access brokers (IABs) to obtain initial access; these IABs primarily leverage phishing campaigns to steal credentials.  

AI-Driven Gmail Phishing Attacks  

With more than 2.5 billion users, Gmail is a prime target for attackers; a recent hyper realistic scam highlights the danger of AI-driven phishing attacks on the service. The campaign pairs AI‑generated voice calls with convincingly spoofed emails to pressure users into acting on a fake Gmail account recovery attempt.  

Microsoft ADFS Phishing Redirect 

In a technique that combines legitimate Microsoft Office links with Active Directory Federation Services (ADFS), attackers redirect users to a phishing page that steals Microsoft login credentials. This phishing attack starts with a target clicking a malicious sponsored link in Google search results; from there, a series of redirects lead victims to unknowingly hand over their login information.  

How to Recognize Phishing Scams  

Even as phishing grows more sophisticated, campaigns will typically feature at least one red flag. Some of the most common phishing giveaways are:  

• Urgency, fear, and other pressure tactics: Messages pressuring immediate action to avoid consequences are designed to force a quick response.  
• Suspicious links: Mismatched domains, shortened URLs, and malicious sites disguised by subdomains are common tricks to hide scam links.  
• Unexpected attachments: Unrequested files and attachments should raise alarm bells.  
• Poor context: Requests that don’t align with normal workflows, such as asking for money or sensitive information, are a common hallmark of phishing scams.  
• Spoofed addresses: Subtle misspellings may make senders appear legitimate at first glance.  

Training employees to spot these indicators remains a cornerstone of phishing defense, but it’s only one piece of the puzzle. To effectively mitigate phishing risks, organizations should prioritize a multi-layered approach that protects against human error. 

Prevent Phishing Attacks: Best Practices for Blocking “Successful” Scams  

Phishing attacks target vulnerabilities in humans rather than tech, making them uniquely difficult to prevent – especially when some employees’ roles anchor largely on opening messages from unknown senders.   

Rather than trying to block all phishing messages, the most effective defenses prioritize preventing successful phishing attacks. These strategies keep an organization secure against phishing scams, even if an employee accidentally clicks on a malicious link or attachment.  

Enforce Robust MFA Everywhere  

Even if a phishing campaign successfully steals credentials, they become useless to an attacker if all privileged access and sensitive systems are protected with multi-factor authentication. Importantly, not all MFA approaches are created equal – simple MFA strategies, such as text messages or push notifications, can be bypassed with various forms of phishing.  

Implement Comprehensive Microsegmentation  

Phishing is often the first step in a broader security breach – once inside, attackers move laterally to escalate privileges, deploy ransomware, or exfiltrate data. Microsegmentation prevents lateral movement by isolating every asset in its own secure zone. Even if a phishing attempt succeeds in providing initial access, the attacker’s blast radius is immediately contained with microsegmentation.  

Prioritize Security Awareness Training  

As attackers continue refining lures with AI and building multi-channel scams, employees remain a key line of defense against phishing. Regular, updated training helps staff build the awareness to spot and report threats. 

How Zero Networks Neutralizes Phishing Attacks Automatically  

While phishing scams are likely to continue accelerating in volume and sophistication, Zero Networks makes it easy to neutralize attacks with layered security controls that prevent phishing attempts from becoming widespread security breaches:  

• Automated microsegmentation: Every asset is proactively isolated, ensuring that even if a phishing scam yields initial access, attackers cannot move laterally.  
• Network-layer MFA: Just-in-time MFA that protects privileged access, legacy applications, and sensitive systems can block credential theft from escalating into privilege abuse.  
• Adaptive policy creation and enforcement: By dynamically evolving rules alongside network changes, Zero prevents phishing attacks from exploiting unknown security gaps.   

Request a demo to find out how you can proactively protect your organization from sophisticated phishing attacks.