Messaging spam and phishing in Classifieds marketplaces

How the attack works

1. The sender opens conversations with listers through the classifieds messaging route, using an enquiry that appears to relate to a property, vehicle or other advert.
2. Fake accounts repeat the approach across many listings, distributing outgoing messages so each sender contributes only part of the campaign.
3. The messages steer recipients towards an external payment page, a claimed courier arrangement or another channel presented as necessary to complete the transaction.
4. When accounts are restricted or messages reported, related senders continue the same operation through other sessions and newly prepared account identities.
5. Affected users report suspicious contact or a loss, and the moderation team must connect senders, message requests and earlier restrictions to understand the campaign.

Why it gets through

Messaging is where a listing becomes a conversation. Users expect practical questions about collection, delivery or payment, which gives a scammer plausible reasons to introduce a link or move the exchange elsewhere. A message can arrive within the platform’s trusted interface even though the sender’s intention is to redirect the user towards a process the marketplace does not control.

Account-level restrictions can miss the combined activity of many senders. Each account may contact relatively few people while the overall campaign reaches a wide group of listers. If an investigation starts only from the reported message, the earlier registration and session relationships between senders may remain difficult to see, allowing related accounts to keep approaching users after one is removed.

Legitimate buyers, agents and businesses can start several conversations quickly. Volume or a shared network alone cannot establish abuse. Linked account activity helps define what deserves review, while the marketplace retains responsibility for interpreting message content and deciding whether a conversation violates its rules.

The message reply rate can fall when listers learn to distrust unfamiliar enquiries. Time spent answering implausible payment stories makes legitimate messages easier to overlook. Review how genuine conversations progress, using the messaging records available to the business, so that increased message volume is not mistaken for stronger demand or more successful connections between buyers and listers.

Cost per abuse investigation grows when a campaign spreads across sender accounts that appear unrelated. Trust and safety teams compare reports, restrict senders and assess whether other recipients need attention. Rebuilding the same connections under separate case references consumes capacity that could otherwise support difficult moderation decisions and users who need an individual response.

Messaging-related abuse report volume can remain high even after individual senders are removed. It captures the recurring burden users bring back to the platform, including concerns about external payment requests. Assess these reports alongside legitimate conversations when tuning restrictions; a lower outgoing message count does not establish that the people using the service are better protected.