The curious case of "Crimeflare / cloudflare-tor" .onion failed connections

The curious case of “Crimeflare / cloudflare-tor” .onion failed connections

  • Linux x64 / Debian Sid

  • Tor Browser v.11.0.6 (desktop)

  • Tor Browser Safest Security Level

Right after I launch Tor Browser, In the Tor log, I notice the following each and every time:

[NOTICE] Closed 1 streams for service cflarexljc3rw355ysrkrzwapozws6nre6xsy3n4yrj7taye3uiby3ad.onion for reason resolve failed. Fetch status: No more HSDir available to query.

This happens before I even touch the keyboard to surf the web via Tor Browser. It also occurs later on during the day/night usually with the same error message but sometimes with 2 - 4
times the amount of error listing.

When I search for this .onion some pages come up with “Crimeflare / cloudflare-tor” but without further explanation.

What is this and why is it occurring?

If it helps any, I’m connecting directly and not using bridges, VPN, or anything else. I’ve also used different Guards but it doesn’t seem to matter. I have no custom settings in torrc / torrc-defaults files (except once, to reveal the source of this .onion error being ‘scrubbed’).

What I can’t figure out is why this happens when you haven’t accessed a page yet.

Anyway, basically it should be like this: You are visiting a page that has Cloudflare embedded in some way.
Cloudflare sends an RFC 7838 - HTTP Alternative Services header and the submitted resource is not accessible.
This behavior is also documented in a bug in Gitlab Cloudflare alt-svc Onion Service unreachable (#40739) · Issues · The Tor Project / Applications / Tor Browser · GitLab

You could now tell Tor Browser to ignore these headers. However, I do not recommend this. But at least it should help you understand what’s going on.

1 Like

Indeed! This is why I thought to post about it as it seemed rather strange. Thanks very much for the links and information!

Moreover, I’ve noticed a few other odd entries in my Tor logs, including one request to access my local system, which was denied. Things got weird after one particular update, I may simply do a clean reinstall of Tor Browser and see if these .onion errors stop. I may test TB alpha version as well to see whether this is only an issue with stable on my system.