Ransomware and Phishing: What Every SME Leader Needs to Know

Phishing and Ransomware Explained

Before looking at how to defend against these threats, it is important to understand how phishing can lead to ransomware.

What is phishing?

Phishing is a type of social engineering attack in which a malicious actor sends a fraudulent message to trick someone into sharing sensitive data, clicking a malicious link, or making a payment.

Email is the most common channel for a breach. Phishing can also happen via text message (smishing), a phone call (vishing), a QR code (quishing), or a chat interface on a company platform.

Modern phishing is very convincing. With generative AI, an attacker can write a credible phishing email in minutes. According to ENISA Threat Landscape 2025, more than 80% of phishing emails identified in the EU used AI-generated content.

What is ransomware?

Ransomware is a type of malware that locks a company out of its own data. The attacker encrypts files, servers, or entire systems, then demands a payment in exchange for the decryption key.

Today, attackers also steal a copy of the data first and threaten to publish it if the ransom is not paid. This is known as double extortion, and it is now a common practice.

According to ANSSI, the French national cybersecurity agency, data exfiltration without encryption rose 51% in 2025, as criminal groups find this approach easier to monetize and harder to detect.

Why these two threats dominate the cyber landscape

Phishing is the most common entry point for a cyberattack on your business. The European Agency for Cybersecurity (ENISA) reported that phishing is the intrusion vector in the majority of cyberattacks in the European Union.

Ransomware is the malware most often deployed once attackers are inside, because it is the most direct way to monetize the attack.

Phishing-as-a-Service and Ransomware-as-a-Service platforms now let lower-skilled criminals run sophisticated criminal campaigns at scale. Established ransomware groups like LockBit, Akira, and Qilin operate like businesses, complete with affiliate programs and customer support for victims negotiating payment.

Why SMEs Are Especially Vulnerable to Ransomware

Small and mid-sized businesses are a preferred target for both phishing and ransomware attacks.

Why SMEs are targeted:

• Limited security resources
• Lower employee awareness
• Valuable digital assets (customer data, intellectual property, etc.)
• Dependence on external IT providers

This combination makes SMEs easier to breach and attractive targets once attackers are inside. The median ransom payment recorded in the Verizon DBIR 2025 is $115,000, highlighting the material financial impact a single incident can have on a mid-market company.

The Financial and Operational Impact of a Ransomware Attack

The real cost of a ransomware attack

The ransom a company pays to recover data is not the only cost. It also includes incident response cost, legal counsel, customer notification, regulatory fines, and weeks or months of degraded operations, lost sales, and reputational damage.

For a French SME, ANSSI and CESIN data place the average direct cost of an incident at €50,000 to €60,000, with one in eight companies facing losses above €230,000.

Paying the ransom does not guarantee you will recover your data. It also offers no guarantee that the criminals will refrain from selling the stolen data to other attackers. And every payment perpetuates the criminal business model and provokes new attacks. For these reasons, most national cybersecurity agencies, including ANSSI in France, advise organizations not to pay. According to the Verizon DBIR 2025, 64% of ransomware victims now refuse to pay.

The long tail impact of phishing

Phishing damage is not limited to ransomware. A successful phishing attack can lead directly to wire fraud, business email compromise, and customer data theft. Stolen credentials and personal data often end up for sale on the dark web, where they fuel further attacks against your business, your employees, and your customers long after the initial breach.

The reputational impact is harder to measure, and for public companies it rarely shows up in the share price for long. But for small and mid-market companies, the consequences play out in relationships with insurers and your customers.

How Phishing Leads to Ransomware

A ransomware incident rarely starts with ransomware. It starts with someone clicking a link in a phishing email, or an attacker logging in with a stolen password.

A typical chain looks like this:

• A phishing email or stolen credential gives the attacker initial access.
• The attacker establishes persistence, often through a legitimate remote access tool that the security team does not catch.
• The attacker will move laterally through the network, looking for valuable systems and data.
• Then the attacker will exfiltrate sensitive data, sometimes over weeks.
• Then ransomware is deployed, or an extortion email is sent.

By the time ransomware is detected, the attacker has often been inside for days or weeks, and the damage is done. This is why employee awareness, multi-factor authentication, and credential monitoring are crucial first lines of defense.

Building Resilience

People and credentials

Many successful phishing and ransomware attacks exploit a small set of recurring weaknesses: stolen passwords, unpatched software, and gaps in employee cyber awareness training.

Multi-factor authentication is an important control. Passkeys or hardware tokens are stronger than SMS codes, which attackers are now able to bypass. Strong password policies, prompt revocation of access for departing employees, and a clear segmentation of admin and standard accounts also reduce the number of people with access to sensitive data.

Patching matters too. Many ransomware attacks exploit known vulnerabilities for which a fix has been available for months. A regular patching cadence closes that gap.

Employee awareness training is effective when it is regular, role-specific, and tested with real phishing simulations. According to the Hiscox 2025 report, 70% of SMEs are now increasing investment in cyber awareness training.

Backups and recovery

Whether you can restore without paying determines almost everything about the cost of a ransomware attack. Companies with tested, offline or immutable backups recover in days. Companies without them face the choice between paying a criminal group with no guarantee of getting their data back, or rebuilding their systems from scratch over weeks.

Backups alone are not enough. They have to be tested regularly, because backups that fail in a recovery scenario are common, and they have to be isolated from the production network so attackers cannot encrypt or delete them along with everything else. A documented incident response plan, rehearsed at least once a year, is what turns a backup strategy into actual resilience.

Third-party exposure

Attackers increasingly reach SMEs through their suppliers. If a supplier has access to your systems, an email account at a vendor, or a connection to your ERP, their phishing exposure becomes yours.

Mid-market companies are particularly vulnerable here because their supply chains are long but their third-party cyber risk management is often not risk-based. A basic third-party risk review, focused on the suppliers with privileged access to your data and systems, is one of the highest-return investments an SME can make.

Treating Cyber Risk as a Business Decision

Phishing and ransomware are operational and financial risks. For an SME, a single incident can mean weeks of disrupted operations, lost contracts, and a ransom demand that exceeds the annual cybersecurity budget.

Most SME leaders cannot answer three basic questions about their exposure. Where is the business most likely to be attacked? What would a successful attack cost in euros? Which controls would reduce that cost the most for the least investment? Without those answers, cybersecurity decisions get made on instinct, on the recommendation of whichever vendor is in the room, or not at all.

A quantified cyber risk assessment changes that. It puts a number on the exposure, ranks the controls by financial impact, and gives the leadership team a basis for deciding what to fund and what to defer.