You spend your morning checking bank balances and making payments. You close your laptop, satisfied with a productive few hours. Unbeknownst to you, fraudsters have already hijacked your session with your bank. They are now using your account as if they were you. This is a form of fraud known as session hijacking, and it relies on a specific type of digital vulnerability.
The Digital Key to Your Accounts
Session cookies are the primary target for hackers today. Marijus Briedis, chief technology officer at NordVPN, states that cookies have become the main focus for cybercriminals. In the year leading to June, his company identified 52 billion cookies in stolen data circulating online.
When you log into a website, your device receives a unique session cookie. This temporary data allows you to move between pages without re-entering your login details. It acts as a digital key that keeps the door open while you are active. If you choose to stay logged in or fail to close the session properly, that key remains in the lock.
Briedis explains that an active cookie is like a key already turned in the lock. If a hacker steals this active cookie, they bypass the need for your password. They also often bypass multifactor authentication (MFA) because the system sees a valid, active session. You do not need to give up your credentials for them to gain access.
How Malware Steals Your Session
The theft usually begins with malware on your device. Infostealer malware is often hidden in browser extensions or software you download. Once installed, the malware accesses your browser database. It grabs all active session cookies and sends them back to the hacker.
This process looks like a regular web session to the victim. You logged in. You may have used MFA. The hacker simply takes over the existing connection. You might not realize you are a victim until later. Scammers may use your social media or email to trick your contacts. They could access your bank funds or redirect online shopping orders to charge your saved payment details.
Security alerts may appear, asking if you tried to change account details. However, many victims only discover the breach after financial loss or compromised personal data. The lack of a password entry means standard login alerts often do not trigger.
Protecting Your Digital Identity
Protecting yourself requires vigilance regarding software and browser habits. Briedis warns that infostealer malware is frequently hidden in extensions and third-party software. You should carefully review what you download and install.
Watch for signs that your device is infected. Red flags include sudden performance issues, rapid battery drain, frequent crashes, or a browser that behaves oddly. Redirects, pop-ups, and a changed homepage are also strong indicators of compromise.
Logging out is a critical step that many users skip. Closing a browser tab does not end the session. You must manually log out to invalidate the cookie and make it useless to a thief. Briedis suggests moving passwords out of your browser and into a dedicated password manager. This reduces the number of active sessions stored locally.
Clearing your cookies regularly reduces the amount of data available for theft. If you suspect you have been compromised, run an antivirus scan immediately. Log out of all accounts on every device and change your passwords. While MFA is not a perfect shield against cookie theft, it still offers more protection than a simple password alone.
Public Wi-Fi poses a lower risk for this specific type of theft, but caution is still advised. The most effective defense is maintaining strict control over your active sessions and keeping your device free of malware.
Source: The Guardian
