What Type of Security Breach Redirects Users to Malicious Websites

The short answer: an open redirect attack

The security issue that most directly answers what type of security breach redirects users to malicious websites is an open redirect attack.

An open redirect happens when a legitimate website has a weakness that lets someone change where one of its links sends visitors. The link may begin with a trusted domain, but it can lead somewhere completely different — including a fake login page or another harmful website.

For example, imagine a shopping link that looks like this:

`trusted-shop.example/continue?next=...`

The website may be designed to send shoppers to another page after they click. If the site doesn't check the destination properly, an attacker may replace that destination with a phishing page.

The link still starts with the trusted website's address. That can make it seem safer than a strange link sent by an unknown person.

An open redirect is best understood as a website weakness that attackers abuse. It doesn't automatically mean the site's customer database was stolen. The problem is that the site can be used as a stepping stone to send visitors somewhere harmful.

How an open redirect sends users somewhere dangerous

A normal redirect moves you from one page to another for a useful reason. A product page might send you to a size guide. A checkout page might move you to an order confirmation screen.

An open redirect does something different. It accepts a destination from a link or web request without properly limiting where that destination can be. An attacker can then create or share a link that starts on the legitimate domain and ends at a malicious website.

A simple example:

1. You receive a link to a baby-footwear product.
2. The link appears to use the shop's real domain.
3. You click it and the shop briefly processes the request.
4. You are sent to a fake sign-in or payment page.
5. The fake page asks for your password, card details, or other information.

The harmful page may be designed to look like the retailer you expected. The logo, colours, and wording can all seem familiar. The important clue is often the address in the browser, especially after the redirect finishes.

This is why a malicious website hidden behind a legitimate domain link may get more clicks than an obviously suspicious address. People tend to trust the first part of the link and may not notice where they finally land.

Why attackers use redirects for phishing and fake login pages

Phishing is an attempt to trick you into handing over information by pretending to be a person or service you trust. A fake login page is one common example.

Open redirects can help attackers make that trick feel more believable. Instead of sending you directly to an unfamiliar website, they may first send you through a real-looking link. The redirect can happen quickly, so you may only notice the final page once it's already open.

For a parent shopping for baby footwear, the message might claim that:

• A pair of shoes is almost out of stock.
• Your saved basket needs attention.
• A size recommendation is ready.
• Your delivery address must be confirmed.
• A payment attempt needs to be checked.

You click the product, size, or checkout link. Instead of returning to the shop, it takes you to a page asking for your account password or payment details.

The redirect itself may not steal anything. The danger comes from what the next page asks you to do. Be especially careful if a page you did not expect suddenly asks you to:

• Sign in again.
• Enter your full card number.
• Provide a security code.
• Confirm banking details.
• Download a file or browser extension.

A trusted-looking first link doesn't make the final page trustworthy.

Other ways users can be sent to malicious websites

Not every harmful redirect is an open redirect attack. The terms are related, but they describe different paths to the same unpleasant result: you end up on a website you didn't intend to visit.

Malicious redirects

Malicious redirect is the broader term. It describes a redirect that takes someone to a harmful or deceptive destination.

An open redirect is one possible cause. Other causes can include a hacked website, unsafe advertising code, or software that changes how a page handles links. So, an open redirect is a specific weakness, while a malicious redirect describes the harmful action or result.

Malvertising

Malvertising means malicious advertising. An attacker places or compromises an online advert so that clicking it sends visitors to a dangerous website.

You might be browsing normally, see an advert for children's shoes or a discount, and click it. The advert then redirects you to a fake shop, login page, or another site used for scams.

That isn't necessarily an open redirect in the shop's own website. The advert or advertising network may be the part that was compromised.

Traffic distribution systems

Some attackers use traffic distribution systems to decide where different visitors should go. These systems can selectively send certain people to compromised websites or fake login pages.

For example, one visitor might see a normal page, while another is sent to a phishing page that asks for online banking or payment information. The exact destination can depend on the visitor, the link, or other details about the visit.

This makes the activity harder for website owners and security teams to spot. It also explains why one person may report a bad redirect while another sees nothing unusual.

URL-parsing vulnerabilities

A URL-parsing vulnerability happens when software reads an address differently from the way its developer expects. A carefully changed URL may then be treated as pointing somewhere else.

The CVE-2021-3664 vulnerability is described as an example where attackers could manipulate URL-parsing behaviour and potentially redirect people to malicious websites.

This is different from a simple open redirect setting. In this case, the problem is how software understands the address itself. For everyday shoppers, though, the practical response is similar: check the final address before entering private or payment information.

Security risks of visiting a malicious website

A malicious website can try to push you into several kinds of unsafe action. The research around these redirects specifically connects them with phishing, fake login pages, and attempts to obtain online financial information.

The risks include:

• Giving your password to a fake sign-in page.
• Entering card or other payment details into a scam form.
• Sharing personal information that the page doesn't need.
• Following more links that lead to other harmful pages.
• Downloading something you didn't intend to download.

You don't need to panic if a redirect happens. Simply reaching a strange page doesn't mean your information was taken. The risk becomes more serious if you typed details, signed in, downloaded a file, or followed further instructions.

Close the page if it feels wrong. Don't keep clicking to find out what happens.

How to spot a suspicious redirect while shopping online

Parents and carers often shop quickly, sometimes from a phone while looking after a child. A redirect can be easy to miss. You don't need to inspect every technical detail, but a few checks can prevent a rushed mistake.

Check the final URL

Look at the address after the page finishes loading. Don't judge the page only by the first link you clicked.

Watch for:

• A domain that doesn't match the retailer you expected.
• Misspellings or extra words in the main domain name.
• An address that changes again when you try to sign in.
• A page that uses a retailer's name in the path but belongs to another domain.

A long address isn't automatically unsafe. The key question is which domain controls the page.

Be cautious with unexpected payment pages

If you clicked a product or size link and suddenly see a payment form, stop for a moment. Return to the retailer by typing its known address yourself or using a saved bookmark.

Don't enter card details on a page you reached through an unexpected redirect. A normal checkout may ask for payment information, but it should still be on the retailer's expected domain and appear as part of a checkout you deliberately started.

Use a malicious websites checker

If a link looks suspicious, you can use a malicious websites checker before opening it. These tools can help flag addresses associated with harmful or deceptive websites.

Treat the result as a useful warning, not as a guarantee that a page is safe. A new scam page may not be listed yet. You should still check the final URL and avoid entering sensitive information when the page feels unexpected.

Look at the shopping route

If you want baby footwear, start from the retailer's main website. Search for the product, choose the size, and move through checkout yourself.

That takes a little longer than clicking an urgent message, but it avoids relying on a link whose destination you haven't checked.

What to do after being redirected

If you notice the redirect before entering anything, close the page and return to the retailer through its normal homepage. Don't use the browser's back button if it keeps sending you to the same place. Opening a fresh page can be simpler.

If you entered a password, change it through the real website rather than through the redirected page. If you reuse that password elsewhere, change it there too.

If you entered payment details, contact the relevant card provider or payment service using its official contact route. Explain what happened and follow its advice.

You should also:

• Check your account for activity you don't recognise.
• Keep an eye on payment notifications.
• Remove any download you didn't mean to start.
• Run the security checks already available on your device.
• Tell other family members who may use the same account.

Try to remember what happened without blaming yourself. These pages are built to look convincing, and the original link may have appeared to come from a trusted domain.

How site owners can reduce open redirect and malicious redirect risks

Website owners can reduce these problems by controlling where redirects are allowed to go. A redirect should usually point only to approved pages on the same site or to a short list of trusted external services.

Useful safeguards include:

• Avoid accepting any destination from a link without checking it.
• Allow only approved domains or local paths.
• Show an intermediate warning before sending visitors to another domain.
• Treat unusual URL formats carefully.
• Keep software that handles URLs and redirects updated.
• Review adverts, third-party scripts, and traffic-routing tools.
• Test product, size, login, and checkout links regularly.

Site owners also need to consider the full journey. A safe product page can still create confusion if an outside advert or third-party tool sends shoppers somewhere unexpected.

For shoppers, the main question is simple: Does the final page match the place I meant to visit? If not, return to a trusted shopping page. Verify the URL before entering payment details, and use the site's baby-footwear guides for sizing and product help instead of following an unexpected redirect.