canonical tag exploit... beware of the bot

[minnapple]

Apparently there is a bot checking for errors in canonical tags.

The errors cause little harm UNTIL someone exploits them.

If they exploit the error the site is toast.

This is all I am going to say on this subject, other than check your tags closely.

[edited by: minnapple at 4:08 am (utc) on Feb 24, 2015]

[brotherhood of LAN]

Very cryptic.

My wild guess is it's something to do with not using absolute URLs.

[minnapple]

Sorry, I would like to be more specific, but at the same time I do not want to plant any ideas into the wrong minds.

[ganzojin]

You mean doing negative SEO on wrong canonical url ?

[Shai]

Apparently there is a bot checking for errors in canonical tags.

By a 'bot' I take it you mean an external naughty type spider... not Google.

[rish3]

I think the guess of "using a relative url" is probably right, but with a specific type of error, like this:

<link rel=canonical href=“example.com/content.html” />

Google says it will interpret this mistake like so:

<link rel=canonical href=“http://example.com/example.com/content.html” />

At which point, it ignores the tag, as it's pointing to a page that doesn't exist.

Creates an opening for someone to scrape the content and publish it with an absolute url, maybe even one that ends in the same relative url:

<link rel=canoncial href="http://scraper.net/example.com/content.html" />

Perhaps that creates the impression with the search engines that the scraped copy is the original content?