What is the purpose of hiding spam links in some obscure forum posts?

Question

I'm moderating one small Discourse forum and we, like everyone else, get spammers from time to time. Our forum is small, like 40-60 weekly unique visitors. Our forum requires that each new user's first post must be reviewed by a moderator before it appears and this catches most of the spammers.

Recently we've been getting spammers posting to some older thread without contributing anything new, like writing: "Thank you. This solved my problem." While posts like these are suspicious, a moderator can't block them outright because they aren't against any rules and they might be coming from a legit user who has just created an account in order to thank someone for helping them out.

Usually after their first post is published, the spammers come back a day or two later and they either make a new post or they edit their previous post to include "hidden links", like:

Thank you[.](https://www.SomeRandomSpamURL.com/) This solved my problem[.](https://www.SomeOtherRandomSpamURL.com/) [.](https://www.EvenMoreRandomSpamURLs.com/))

I'm simply curious as to why would someone do this? I understand the purpose of regular spam links where the spammer tries to explicitly divert traffic to some site, but if the link is hidden behind a dot, then 99% of users likely won't ever realize there's a link to be clicked. If they do, then they'll likely realize it's a scam link. It's also not like someone could accidentally hit a dot on a forum post either.

What are these spammers trying to gain by creating these "hidden" spam links?

Answer 1

It could be an attempt to boost the spam sites in search engine results by creating backlinks to it, which is a common SEO technique (although debatable how effective it is, as search engines can often detect this kind of dodgy behaviour).

Answer 2

It's all about search engine reputation, as discussed.

However, it's not going to work on your site. Because you are a conscientious forum operator, so of course you add the meta tag "rel=nofollow" on every URL link that comes from user-generated content aka UGC. (There is also a "rel=ugc" tag but it may be a Google-only extension to the spec). The spec has been around since the late 2000s (the decade).

If you don't use that tag, well, that paints a target on your back.

It can also help, if you are good at this, to rename at least one of the mandatory fields on the signup page, such as the "repeat password" field. These attacks are all scripted, of course; and they are counting on everyone using the stock UI provided by the forum software. Human logins coming off your UI have the correctly renamed repaet_passwrod field; bot logins have the wrong (normal) field name, and are rejected for lack of the field. They're not going to send a human to investigate.

Answer 3

Spam and leaving links is a business nowadays. "Companies" (and I use this term in a very broad meaning) sometimes are getting paid if they leave the spam-url on different sites, and also by the number of days the link is present on the site. Say a few cents per day that the link is available on the site. Employers of those companies seldom look at the actual links, but automatically verify that the link is present.

If you can easily hide the URL in a way that it stays available for a longer time you get more cents. Of course, this is done automatically so the investment is low.

So, they may be scamming the spammers.

Answer 4

In days gone by to get your site to the top of Google, those with a wonky moral compass would leave wikimedia wide open on the site. Within a week, it would have GB of spam, links to which would be posted by an army of bots and sweat workers on many thousands of forums world wide.

Heavily linked to ==> higher score. Then they delete that database and published their app. Redirection could be applied to the backlinks.

Google is wise to this, but it does still happen for legitimate content.