Credential abuse, exploitation of vulnerabilities, or phishing were the initial access vectors in 61% of breaches in 2025, according to Verizon’s 2025 Data Breach Investigation Report.

While new threats present fresh challenges to security teams, reports like this highlight that cybercriminals still favor well-established attack methods and exploit familiar weaknesses. They aim to maximize return on investment, and it’s often the simplest, most reliable methods that still deliver the highest payoff.

Many ‘evolving’ cyber threats are really refinements of long-standing techniques. Flaws buried in widely used web application components like Log4J or React2Shell can introduce vulnerabilities to thousands of organizations, creating a broad base to target.

At the same time, attackers still exploit human factors for the simple fact that it works. That’s why understanding the weaknesses hackers commonly exploit, and taking steps to remediate them, is crucial to break the cycle of preventable compromise.

Old techniques behind modern breaches

While cyber threats grow more sophisticated, the methods have changed far less than the technologies they target. Many modern attacks succeed not through innovation, but through the repeated exploitation of the same fundamental weaknesses.

Spear phishing

Phishing isn’t new, but the human factor remains a key vulnerability. By using artificial intelligence (AI) tools and publicly available data (for instance, LinkedIn profiles), they can craft highly convincing messages to deceive their targets. The delivery has evolved, but the principle hasn’t changed – trick the person to bypass the technology.

Malicious email attachments

Malware hidden in email attachments is a persistent risk plaguing organizations. Malicious macros used to be a common delivery vector, hidden within seemingly legitimate Microsoft Office documents. However, Microsoft disabling macros by default has seen their use as a malware delivery payload sharply decline.

Attackers today are increasingly distributing malware through URLs in emails and PDF attachments, using lookalike domains and convincing formatting to trick even observant targets. IBM identified an 84% increase in infostealers delivered through phishing emails in 2025. These leaked credentials are sold on the dark web and heighten the risk of account compromise.

Log wiping

Users rarely clear logs, so log wiping is a strong indicator that an attacker has infiltrated a network. When attackers erase or tamper with logs, they deprive security teams of critical visibility when it is needed most. Without reliable audit trails, investigators struggle to reconstruct events, assess the scope of compromise or determine the attacker’s next move. Selective log tampering can also mislead responders and delay containment.

Unpatched systems

Publicly documented vulnerabilities are a prime attack vector for cybercriminals. Critical industries like healthcare and manufacturing often rely on older hardware and software that is too expensive or risky to replace. Once exposed, unpatched assets are easy targets. If a vulnerability is known and reachable, it will be exploited.

Why do old attack methods still work in 2026?

The persistence of these methods is not a failure of innovation on the attacker’s side, but a reflection of enduring vulnerabilities within organizations.

Weak identity governance

Even as multi-factor authentication (MFA) becomes more common, environments like service accounts, poor governance of legacy credentials and third-party access create blind spots that attackers readily exploit. While identity has become the new perimeter, it is still too often managed with outdated assumptions and inconsistent controls.

Legacy infrastructure

Many organizations are still dependent on legacy systems that are outdated or running unsupported operating systems. These systems are difficult to patch, costly to replace and frequently excluded from modern security controls. Attackers actively target older assets, knowing that known vulnerabilities can remain exploitable for years.

The human factor 

If the accounting department receives an urgent transfer request from the CEO, or what appears to be the CEO, the instinct is to act quickly rather than question the request. Cybercriminals rely on this reflex, using familiarity and time pressure to bypass technical safeguards. Phishing and other social engineering attacks persist because they exploit predictable human behaviors that are difficult to eliminate through technology alone. 

Inconsistent patching and security policies 

Patch management continues to be a challenge for most organizations, particularly in complex or distributed environments. While critical vulnerabilities are disclosed at an unprecedented rate, many organizations struggle to prioritize, test and deploy patches consistently. At the same time, security policies are often unevenly applied across cloud and on-premise environments. These inconsistencies create predictable gaps where known exploits can be reused with minimal effort. 

The cost of weak security fundamentals

Excessive permissions, exposed services, unsecured backups and poor asset visibility all contribute to an environment where simple attacks can rapidly escalate. For instance, shadow IT introduces unnecessary risk into an organization, where IT teams are unable to effectively track the devices and systems that connect to internal networks.

These issues can accumulate as IT environments grow faster than governance, leaving gaps attackers easily exploit.

Vulnerability risk management: How to protect your business against old weaknesses

Lock down identity first

• Enforce MFA wherever technically possible, including for administrators, remote access and third-party users.
• Audit service accounts regularly and remove stale, shared or over-privileged credentials.
• Apply least-privilege access by default and review permissions as roles change.
• Treat identity as a primary security control, not a secondary IT task.

How Outpost24 helps: Our free Credential Checker gives organizations visibility into exposed credentials on the dark web, allowing teams to act quickly and prevent identity compromise.

Reduce legacy risk

• Identify legacy systems that cannot be patched, upgraded or easily replaced.
• Isolate high-risk systems from the wider network using segmentation.
• Apply strict access controls to limit who and what can interact with legacy assets.
• Monitor these systems continuously to detect suspicious activity early.

How Outpost24 helps: OutscanNX, Outpost24’s Risk-Based Vulnerability Management service, helps you discover, assess and prioritize vulnerability remediation across your network. This includes legacy systems, shadow IT and cloud misconfigurations.

Patch with purpose

• Remember that unpatched systems are potential entry points for attackers.
• Isolate high-risk systems from the wider network.
• Apply patches consistently across cloud and on-premise environments.
• Track coverage to ensure no systems fall outside policy.

How Outpost24 helps: We help organizations identify high-risk systems through our External Attack Surface Management (EASM) product. With continuous discovery of external-facing assets, Outpost24’s EASM delivers actionable intelligence on possible vulnerabilities and attack paths.

Strengthen human defenses

• Run regular, realistic security awareness training focused on common attack methods.
• Reinforce training with simulated attacks to help employees recognize malicious email attachments, phishing scams and other issues.

How Outpost24 helps: Our blog and resources have up-to-date information about the threats facing organizations, and the tools and tactics that help them secure their networks.

Fix cyber hygiene basics

• Maintain an accurate, up-to-date inventory of all assets and services.
• Remove unnecessary services and close unused ports to reduce attack surface.
• Enforce least-privilege access across systems and applications.
• Secure, test and monitor backups to ensure recovery is possible.
• Review configurations regularly to catch small issues before they escalate.

How Outpost24 helps: Our EASM solution combines automatic asset discovery with threat intelligence and flexible penetration testing to help organizations identify and prioritize vulnerabilities across their attack surface.

Vulnerability risk management is a now central part of effective cyber defense. If you’re ready to discover and manage the vulnerabilities hiding in your business, contact Outpost24 to speak to a security specialist.