Email remains the main battlefield for cyberattacks. Industry data show that one in four emails worldwide is spam or malicious, and 94% of malware is distributed via email. Surveys show that nearly 7% of small companies experienced an email-related issue this year. Phishing, ranging from mass spam emails to targeted spear-phishing, leads to a list of ever-growing threats.
Advanced frauds, such as AI-powered deepfake scams and BEC (business email compromise), have already cost victims millions of dollars, including a fraudulent “CEO” call that tricked a firm into transferring $25.6M. As attackers continually develop new methods (from MFA bypass devices to QR code hacks), MSPs must layer security controls and user training to safeguard their customers. In a nutshell, email security is a must-have for MSPs by 2025.
The Biggest Email Security Threats in 2025
1. Phishing and Social Engineering
Phishing is “king.” Nearly a quarter of all fraudulent emails are generic phishing scams, which is why Phishing is the most prevalent threat and is expected to increase this year. The number of phishing scams has increased dramatically, with reports indicating a 4,000%+ increase since 2022. AI tools create more sophisticated attacks. Modern Phishing is usually highly refined and well-designed, and it can fool even the most cautious employees.
Social engineering extends beyond email: nearly 50% of phishing attempts use other channels, including Slack, Microsoft Teams, and social media. MSPs must assume phishing attempts can occur across any channel and train personnel to identify suspicious attachments, links, or requests when encountered.
2. Spear-Phishing and Business Email Compromise (BEC)
Scams targeted at specific individuals pose a significant risk. In contrast to generic Phishing, spear-phishing emails are branded and often impersonate trusted vendors or executives to trick victims into transferring funds or personal information.
Deepfake-powered scams have become a part of BEC. In one instance, a fictitious “CEO” video conference instructed employees to transfer $25.6 million. The attackers are also testing MFA bypassing techniques, using malware that entices users into releasing one-time codes. Anyone who is an MSP customer who handles payroll or invoices is particularly susceptible.
3. AI-Driven Deepfake and Generative Attacks
2025 will see a rise in the use of AI-powered social engineering. Deepfake voice and video recordings enable attackers to impersonate executives via Zoom or phone, and generative AI can create compelling phishing messages at scale.
Surveys indicate that most security professionals expect deepfakes and AI-driven phishing attacks to grow dramatically this year. Many companies admit that they’re not prepared. The solution is to deploy AI-based security measures. Anomaly detectors and machine-learning filtering could identify unusual communication patterns and staff who should be trained to recognise requests outside the band (e.g., by phone).
4. QR-Code and Multi-Channel Phishing
A more recent twist has been “quishing,” in which scam links are embedded in QR codes. Because QR codes obscure the destination URL, they can often bypass filters. According to reports, more than 1 million phishing messages using QR codes were sent within a single month in 2025.
Attackers are also using collaboration platforms such as Teams, Slack, and LinkedIn. About 40% of phishing scams are now extending beyond email. MSPs are advised to advise clients to view links and QR codes from unidentified sources with caution and to choose tools that provide an integrated security solution for collaboration and email apps.
5. Malicious Attachments and Links
Email remains the most common vector for spreading malware. Approximately 1 in 100 emails is malicious, and a large proportion of executable attachments contain malware.
The attackers hide trojans and ransomware in archives, documents, and fake invoices. In fact, even “harmless” ZIP or PDF documents can contain harmful malware. MSPs need to enforce strict filtering through sandboxing and AI. Block executable files as default, and inform users not to enable macros or provide credentials in suspicious pop-ups.
6. Account Takeover and Credential Theft
If hackers steal login credentials or passwords, they could send fraudulent emails or launch additional attacks within the network. Credentials stolen are often the initial point of entry for ransomware.
MFA helps, but it isn’t 100% secure; attackers are developing MFA-bypassing tools. The threat of supply chain compromises is also increasing, as attackers exploit partners’ compromised email accounts to steal information from other users. MSPs need to ensure MFA worldwide to detect login anomalies and credential rotation. They also need to implement domain-level security measures like SPF, DKIM, and DMARC.
7. Insider Risk and Human Error
The weakest link remains humans. Research shows that human error accounts for 95% of breaches. Phishing only works when employees click on or follow the instructions.
The good news is that organisations that run regular phishing simulations have 6 times fewer clicks on phishing attempts in real email. MSPs should conduct fake phishing campaigns for their clients, monitor risky behaviour, and provide guidance. Simple practices, such as confirming requests for financial transfers by phone,e can help prevent significant losses.
Strengthening Defenses: Best Practices for MSPs in 2025
To protect themselves from these threats, MSPs must implement layered defences that combine technology policies, detection capabilities, and user alerts.
- Strong Authentication & Policies Enforce: MFA everywhere, publish and keep track of SPF, DKIM, and DMARC records, and make sure that no email is faked to appear as coming from the domain of your client.
- Encryption and Secure Transport: Use TLS to secure data in transit and end-to-end encrypt sensitive data. Automate encryption policies to safeguard the health and financial data.
- AI-Powered Threat Detection: Use the latest email filters and AI-driven tools that adapt to evolving attack methods. AI models can detect subtle deviations that static filters can’t detect.
- Server Hardening & Monitoring: Regularly patch email servers and apply secure configurations. Centralize your logs and look for anomalies, such as bulk forwarding rules or outbound email.
- Integrated Cloud Email Security (ICES): Moving beyond the outdated gateways. Use the latest ICES solutions that connect directly into email systems and utilise behaviour analytics to detect contextually relevant events.
- Security Awareness Training: Engage employees constantly with exercises and practical examples. Create a culture that encourages notifying of suspicious messages.
- Incident Response & Backup Plans: Automate alerts for unusual login attempts or email activity. Maintain regular mailbox backups and test disaster recovery procedures.
- Client Communication & Education: Send threat intelligence updates to SMB clients to ensure they are aware of risks, including deepfake scams and QR Phishing. Assist them in budgeting for modern security.
Conclusion
Email will be the top attack vector through 2025. Hackers are using Phishing and AI-powered deception, as well as fraudulent access to credentials, and malicious payloads to beat out old defences. For MSPs, the task is simple: create layers of security that incorporate the latest technology, robust policies, and ongoing user education.
Companies such as SecureTitan, when coupled with the right tools and best practices, could provide MSPs with the framework they need to keep up. By treating email security as a primary concern rather than a secondary one, MSPs can protect clients from costly breaches and become trusted security partners.