A URL is considered suspicious due to matching indicators of similar malicious URLs.

Risk Score represents the percentage of sites with similar features to the site you’re researching which we've found to be penalized or banned by Google. Spam Score is based on our machine learning model which identified 27 common features among the millions of banned or penalized sites in the data we fed it.

A high-Risk Score for your site, or a site you're looking at, doesn't mean this site is necessarily spammy. It's a sign that you should do some more investigation into the quality and relevance of this site. Read more about how to use Risk Score.

This does not mean that your site is definitely spammy. The percentage represents a wide variety of potential signals ranging from content concerns to low authority metrics.

Since this is based on correlation with penalization rather than causation, the solution isn't necessarily to change these factors on your site. If you have not had any penalties you shouldn’t be concerned about a Low or Medium score. It is best to use this percentage figure to judge the quality of inbound links to your site, giving you a signal to help you determine which of those links needs some further investigation and, perhaps, even removal.

To know exactly the reason, it would be necessary to do an exhaustive analysis of the domain.

How accurate is this, and how can I rectify this?

In Brand Backlinks, you can see that your domain has backlinks from several domains with a higher Risk Score. Your domain is matching indicators of similar malicious URLs. This is one of the biggest problems.

The process of rectifying this issue is not easy, but you can do it with patience.

Here is some advice:

Manually, you must submit a request to delist the domain to the respective blacklist authorities.

Here is a link with information about this.

https://transparencyreport.google.com/safe-browsing/search?url=https:%2F%2Fround10boxing.com

https://geekflare.com/website-malware-removal/

Disavow High-Risk Score backlinks.

You have to analyze all high-risk score links for one and disavow them.

Here is a link with information about disavow links.

https://www.greenlanemarketing.com/resources/articles/step-by-step-disavow-process/