They have a convincing reason for the new number.

"My screen broke, using a temporary phone" or "it is in for repair, messaging from a PC" is the script. There is one check: do not reply — call the family member's original number. If they say calls do not work, contact another relative.

They only want a photo of my ID. Is that OK?

No. An ID photo plus card details can be used to open phone lines, online bank accounts or loans in your name. If you already sent them, register with Korea's FSS exposure-prevention system (pd.fss.or.kr) and M-Safer (msafer.or.kr) right away.

They sent a link asking me to install an app.

It is a remote-control or malicious app. Once installed, they can operate your phone and move money through your banking apps. If you installed it, switch to airplane mode and call your bank from another device.

"Mom, My Phone Broke" Messenger Scams

Problem

A message arrives from an unknown number on KakaoTalk or SMS: “Mom, my screen broke so I am using this number for now. Can you do me a quick favour?” Then comes the request — a photo of your ID, your card number, or “just install this app from the link”.

Family impersonation starts with conversation, not a link. It uses worry for a child or parent and sets up, in advance, a plausible reason why calling will not work.

Symptoms

An unknown number, or an account whose profile photo copies a family member.
“My phone broke” or “it is being repaired”, so the usual number does not work.
They avoid calls and insist on messages.
They ask for an ID photo, card number or PIN, or a verification code.
They send a link to install an app, or urgently ask for a transfer.

Three checks

1. Call the original number. This alone settles most cases. Do not reply — call the family member’s usual number. If they do not pick up, ask another relative. A real request can wait a few minutes.

2. Never send ID, card details or codes. Not even to family over a messenger. That information is enough to open phone lines, online bank accounts and loans in your name.

3. Never install the app. An app sent by link is a remote-control or malicious app; installing it lets them operate your phone.

Diagnose with DechoNet

If the message contains a link, paste it into the phishing link check. It shows whether it leads to an app (APK) download and whether the domain is newly registered. If there is no link, only talk, rely on the three checks above.
Domain registration lookup shows the link domain’s registration date.
Lookalike domain detection finds addresses imitating known services.

Resolution Checklist

Do not reply; call the family member’s original number.
Do not send ID photos, card numbers or verification codes.
Do not install apps sent by link.
Agree on a family rule: urgent favours are always confirmed by a call.
Screenshot the conversation and report it (Korea: 112 or ecrm.police.go.kr).

When to Escalate

If you sent money, ask the police (Korea: 112) and your bank for a payment stop now.
If you sent an ID photo or card details, register with pd.fss.or.kr and msafer.or.kr and ask your card company to reissue the card.
If you installed an app, follow the “you installed an app” steps in what to do after clicking a smishing link.

Paste the message and check it now

Paste the whole message or just the link. The text is not stored; each link is followed to where it really goes.