Malware is software designed to harm systems or misuse their resources. It can steal credentials, expose private data or give attackers control of a device.

The term covers different behaviors rather than one specific attack. Some malware encrypts files for extortion, while other programs quietly collect information or let an attacker operate a compromised machine. For customer identity teams, the consequence may appear as account abuse on a legitimate service even though that service was never infected.

Common forms of malware

Viruses attach to other files or programs, while worms can spread between systems. Trojans disguise malicious functionality within software a person may choose to install. Ransomware blocks access or encrypts data to support extortion.

Spyware and information stealers focus on collecting data. A keylogger records typed input; other components may extract saved browser credentials or session cookies directly. These categories can overlap within one malicious program, so naming a malware family does not describe every action it can perform.

Infection can begin with a deceptive download or exploitation of a software vulnerability. Mobile devices are also targets, with platform-specific installation rules and permissions shaping what an attacker can do.

How a device infection becomes account fraud

Suppose a customer installs a malicious browser extension that obtains reusable session material. An attacker may attempt to replay it against the customer’s account without knowing the password. If the service accepts the stolen session, another login challenge may never happen.

A different infection might capture credentials that the attacker later tests across multiple sites. The resulting activity can look like ordinary sign-ins until account behavior or device context exposes a problem. A password reset can address the stolen password, but it does not remove malware from the customer’s device.

Controls at the device and the service

Maintained software and restrictions on untrusted applications reduce opportunities for infection. Endpoint protection helps detect malicious activity and supports device investigation. Cleanup or recovery needs to address the compromised system itself.

The online service has a separate job: protect the account when requests arrive. Strong authentication reduces exposure to stolen passwords, while session controls and risk assessment help address abuse after login. Sensitive changes may need fresh verification through an appropriate trusted channel.

When compromise is confirmed, coordinate credential replacement with revocation of affected sessions. Asking the customer to enter new credentials on an infected device can expose those credentials again. Customer identity controls can limit misuse of the account, but they are not an endpoint malware-removal service.

Frequently asked questions

Is every computer virus malware?

Yes. A virus is one type of malware. The broader term also includes threats that do not attach to files or spread like a virus.

Can malware bypass a strong password?

Malware can capture a password during use or steal an already authenticated session. Password complexity alone does not address those mechanisms.

Does multi-factor authentication prevent all malware-related fraud?

No. It helps protect sign-in, but a compromised device may expose sessions or allow actions after authentication. Device remediation and account-level controls remain necessary.

Related: Mobile Malware · Device Takeover · Session Hijacking · Account Takeover (ATO) · Credential Stuffing · Data Breach