False positive for slashdot.org when using Fanboy's Annoyance List

[agoralski]

When using Fanboy's Annoyance List in nextdns I have slashdot.org blocked completely, it resolves to 0.0.0.0.

When I disable it, slashdot.org opens fine. But that's not a problem with the list itself, because when using the same list with uBlock extension for example, slashdot.org opens just fine. So maybe there's a bug on how nextdns is processing this list?

[Voltairine-de-Cleyre]

@agoralski -

So maybe there's a bug on how nextdns is processing this list?

It's that NextDNS does not consume the included white lists in any respective "adblock-style" formatted list. It indeed causes issues such as the one you've encountered.

[Sduibek]

So this was reported 2 years ago and is still happening today.

Seems a pretty basic and important issue to resolve - you know, to have the service actually support the lists it uses.

NextDNS is just never gonna fix it i guess, or...?

[breadtk]

Still an issue as of today.

[hagezi]

@rs @romaincointepas

Do not extract rules with the $third-party modifier from adblock filters for using in DNS lists

||slashdot.org^$third-party

[romaincointepas]

Without accepting $third-party and/or $popup those ABP lists would be empty. We will add a warning in the UI for those lists.

[joshuataylor]

How would it be empty? Am I misunderstanding something?

$third-party rules are used for adblockers to block requests to third-party, so if you're on slashdot.org, everything else will be blocked by your adblocker. This has been the case since it was implemented in 2008 by Adblock Plus, it's also used by uBlock.

Let's take a look at https://secure.fanboy.co.nz/fanboy-annoyance.txt for example (their uBlock list is similar).

It has 57,760 results.

If we search for ^$third-party, this shows 698 results.

So it should be fine?

Alternatively, you could skip everything from:

!-------------------------Third-party blocking rules--------------------------!

to

!--------------------------Specific blocking filters--------------------------!

[hagezi]

Without accepting $third-party and/or $popup those ABP lists would be empty. We will add a warning in the UI for those lists.

Parse Adblock lists for DNS as follows:

# Valid domain regex
regex="(?=^.{4,253}$)(^(?:[a-zA-Z0-9](?:(?:[a-zA-Z0-9\-]){0,61}[a-zA-Z0-9])?\.)+([a-zA-Z]{2,}|xn--[a-zA-Z0-9][a-zA-Z0-9\-]*[a-zA-Z0-9])$)"

url="https://secure.fanboy.co.nz/fanboy-annoyance.txt"

curl -sL "$url" | sed -e 's/^[[:space:]]*//' | grep ^\|\|.* | sed 's/[\|^]//g' |
    sed 's/$important,all//' |
    sed 's/$important//' |
    sed 's/$all//' |
    sed 's/$document//' |
    sed 's/$doc//' |
    sed 's/$1p//' |
    grep -P "$regex"

With this fanboy list you get 172 valid domains for DNS. Everything else leads to false positive domains. Adblock lists are not made for DNS but for content blockers.