Also by us: DMARC Guy·Reporter

Why There's No Customer Logo Wall Here

Your company and six of your providers: three publish their customer list, so a criminal reads your name on their website, breaches them once, and their key opens your door; three keep names private

Many providers show a row of customer logos to look trustworthy. We don't, on purpose.

LastSpam sits in front of your inbox: every message to your organisation passes through us before it reaches you. DMARC Guy, the same team, reads the reports that say who sends email as your domain. A company that holds a piece of your infrastructure should not be advertising whose infrastructure it is.

What a logo wall tells an attacker

Nobody breaks into a well-defended company through the front door. They go through a provider that already has a key. The first step is finding out which providers those are, and vendor websites answer that question for free.

  1. Who is reachable through this vendor. Fifty logos on one page is a list of fifty organisations that all share the same door. Compromise the vendor once, and every name on the wall is on the other side of it.
  2. Which emails your staff will trust. If it's public that you use a given mail filter, CRM or ticket system, a forged "notification" from that brand looks normal to your people. No breach of the vendor needed; the name alone does the work.
  3. What access that vendor holds. Each provider type implies a known kind of access: DNS login, admin role in your tenant, API token, remote-control agent. Name the vendor and you've named the key.

Every provider that names you is one more door with your name on it

This is a common practice, and an avoidable one. Here is what each kind of provider typically holds about an organisation, and what a public "they are our customer" hands to someone planning an attack.

ProviderWhat they usually holdWhat a public listing gives an attacker
Email filter / MX← usYour entire inbound mail stream, often an admin connector in Microsoft 365 or GoogleA forged quarantine digest or "release this message" link that looks exactly right
DMARC / email-auth service← usRecords in your DNS, your aggregate reports: a map of everything that sends as your domainWhich sending platforms you use, and a brand to impersonate for a "fix your DNS" request
DNS / domain hostLogin that can redirect your mail and websiteKnows which registrar's password reset to phish; a fake "renew your domain" email from the right brand
CRMEvery customer, contact and deal you haveThe export worth stealing, and the login page to clone
ERPSuppliers, bank details, invoicesThe raw material for invoice fraud: who you pay, how much, when
Ticket / help-desk systemInternal problems, passwords pasted in tickets, who your IT people areA believable "your ticket #4821 was updated" lure to the exact people who handle access
Mass-email platformYour subscriber list and the right to send as your domainKnows which platform to compromise to mail all your customers as you
IT consultant / MSPAdmin credentials and a remote-control agent on every machineThe single most valuable target: one firm, all of its clients at once
Backup providerA full copy of everythingWhere to go for the data when the live systems are locked down

Six providers, six doors. If three of them published the relationship, three doors have your name on them before anyone has touched a keyboard.

This is how it actually happens

None of these started with the victim's own network. All of them started with a provider that already had a key.

What we do instead

No names, anywhere. Not on this site, not in a slide deck, not in a case study without the customer's own written choice to be named. We treat your name the way we treat your mail.

References on a call. Want to talk to someone who uses us? Press the green button at the top of this page. We'll put you in touch with a customer who has agreed to take the call, one to one, nothing published.

What we can say. LastSpam has filtered business email since 2002, for firms, school boards and public bodies in Québec, Canada and the United States. The live threat map on our home page shows today's traffic as it happens, not a logo. DMARC Guy, the same team, handles email compliance and delivery problems for organisations from a few mailboxes up to 40,000 accounts. For the rest, ask us on a call.

Three questions to ask any provider

Not just us. Your DNS host, your IT firm, your CRM, anyone with a key.

  1. Do you publish your customers' names anywhere, including sales decks and social media?
  2. Who on your side can see our name, our data and our access, and how is that reviewed?
  3. If you were breached tomorrow, what exactly could someone do to us with what you hold?

A provider that answers all three without hesitation is one you can keep.

Talk to the person who runs it

The button at the top of this page is green when Jeff is available for a live video call, amber when he's already on one, and grey when he's away. Grey sends you to the contact form. Either way you reach the person who runs LastSpam, not a sales desk.

Jean-François Bourdeau · LastSpam · DMARC Guy · Montréal, Québec. Email security since 2002.