Is cookie 'test' with value 'testvalue' set by Matomo?

bigboy · February 22, 2021, 12:21pm

Hi,

I maintain several websites and for all of them I use Matomo with settings per site.
In all of them I find a cookie ‘test’ with value ‘testvalue’ and an expiry time of 12 sec. and attributed to the domain of the respective website. It’s named only ‘test’, not ‘_pk_testcookie’.
Could it be set by Matomo nevertheless?
It appears also on websites that use no other javascript but Matomo and are not base on a framework.
If not set by Matomo, has anybody a tip who could be responsible for it?

Thanks in advance
-bigboy

Lukas · February 22, 2021, 12:31pm

Hi,

Yes, a cookie test:testvalue is set by Matomo:

github.com

matomo-org/matomo/blob/4.x-dev/js/piwik.js#L3382-L3394


function isPossibleToSetCookieOnDomain(domainToTest)
{
    var valueToSet = 'testvalue';
    setCookie('test', valueToSet, 10000, null, domainToTest, configCookieIsSecure, configCookieSameSite);
    if (getCookie('test') === valueToSet) {
        deleteCookie('test', null, domainToTest);
        return true;
    }
    return false;
}

There is no way to find out if cookies can be set than to set one and check if it exists (and delete it afterwards) so that’s what matomo does when you call setCookieDomain.

You are right that something like pk_testcookie would be a better name.

See