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I don't know if this is the right place for this, I need to warn people about a new trick that hackers are using to drain bank accounts and crypto wallet.

someone living next to me lost over 2000$ in his bank account and tokens in his metamask all wiped out..the last thing he did before he started receiving debit alert is opening a PDF sent to his mobile number, that's it.

The same PDF that's been sent to me several times and since the sender hidden their number I can't block them for good, I just knew it feels wrong downloading a PDF file that I wasn't expecting.

Many people have already became a victim, most are not into crypto and they are blaming the banks.

https://i.imgur.com/YLP3a5e.jpeg

If you are from Nigeria 🇳🇬 be very careful, the hackers form any +234 numbers and send them this PDF file, there are more than 5 people within my area that have received the same PDF, there are too many news about money vanished from bank accounts that's why many people are scared now.

I have deleted this shit over 20 times already but the sender keeps sending it back, if you know how I can block the sender ( hidden number ) please do share. God bless

While this is a more-clever scam compared to most, it's definitely not a new one. You can easily dodge this by simply not randomly download any file that's been unexpectedly sent to you — and better yet, not randomly open files.

I am from Nigeria and I believe I have also received similar messages containing some sort of file for download from unknown numbers. They were of course promptly ignored and I blocked the number IIRC. I don't think I ever got a repeat of the message.

Your friend's loss is unfortunate and I hope he can recover from it. He should consider moving any left over assets on the device to a new one and wipe the device clean to prevent a reoccurrence.
Also advice him on having a separate device specifically for holding assets to prevent falling victims to malwares or phishing links.

Android? Depends on the version and if there are no custom things installed from the carrier itself but usually blocking unknown numbers from the call settings option> block numbers > block unknown numbers slider > will block messages too, at least on my phone. If that doesn't work you can install Truecaller!

But seriously, why would someone download and open a file received from a stranger? Just why?
This is no different than opening a spam email attachment!

Difference cases in my country about hack or steal bank account assets due new application installed on our mobile phone, I am new with your method sharing about how possibility with pdf file sending to our mobile phone can loss all assets between bank and cryptocurrency have. Due our number participants in many kinds or airdrop I don't think how keep securing and make private it, actually in my country have new rule adopted for every one not allow having more than one mobile phone number.

Great way and I will try how to protect my phone number from unknow, usually many time I received call from financial insurance and your method will help me protect not received yet call from them.

Hackers do not give up easily and every time they surprise us in unimaginable ways. But in this case it is surprising that they actually succeeded in draining the bank accounts since these transfers can be traced. Also, transfers are supposed to be confirmed via e-mail and phone number. Did they really succeed in breaching all these protection measures using the pdf file?

As for Metamask, there are warnings issued a week ago about a new scam method called "address poisoning", which makes the victim send crypto to another address of the hacker, different from the original address he wants to send to.
https://cointelegraph.com/news/metamask-warns-crypto-users-about-address-poisoning-scam
Source : https://www.bleepingcomputer.com/news/security/metamask-warns-of-new-address-poisoning-cryptocurrency-scam/

You don't have to move it in other board as Beginners & Help is fine. I don't know if what you shared is true or not but if you ask me then it is a good find and you even share it here in this forum. Base on the image you provided, I think it happen to yourself right and it's on mobile devices. If I am wrong then what device did you use when you noticed this hack or did you find it somewhere else and share it here. Many people including myself doesn't want to download anything like PDF (whitepaper, Guide and more) from a casino especially from a new one.

Thanks OP for this I have been getting unending messages just like this practically everyday. I thought it was from maybe a service or something but I never took it any where serious at all and did not even see it as a possible threat.

I have developed a natural knack not to get too eager to open any content that is not verifiable, from someone I don’t know. This knack has saved me from this threat right now.

I am not from Nigeria but this warning is definitely helpful. Because now hackers are using this technique in certain countries, maybe in the future hackers will use this technique in other countries as well. In fact, now you have to be careful before opening any message from a stranger, because a little carelessness can lead to big losses. Thanks OP for bringing up this hacker trap trick here.

Despite how harmless this hacker strategy I still believe it is something every cryptocurrency shouldn't have to be a victim of since we both know mobile phones are always vulnerable to attack especially when downloading something from unknown or untrusted source.


This is a nice idea. For people who don't have Truecaller due to privacy and other reason to block unknown user messages. Go to your SMS box> Option > Spam & blocked > Option > Blocked numbers > Block unknown/hidden numbers.

This information is extremely useful, as one can easily download a PDF sent to his phone to check even if he does not know who sent it, simply out of curiosity to see what it contains. Small pieces of advice like this can help people protect their accounts. If it had been sent to me, I would have downloaded it without hesitation, but this news has helped me understand that it could be hackers attempting to invade one's privacy. The best method is to remove your assets from your phone's wallet apps.

I used to receive unknown, spam and random emails that contains .pdf files but I delete the emails and ignore them. If someone who's too curious in knowing all of them, you can read the message and you'll understand and definitely get to have the idea that it's a clear scam or attempt to hack.

I don't know if there's an attached malware with such pdf files but I don't want to go deeper with that and it's better to just don't open unsolicited email or links.

Well noted OP thanks for the heads up, although i have come across so many people in my neighborhood that have been bitterly complaining on how there account have hacked and their money stolen. I myself have personal given some lessons to some persons in my area on what to do and what not to do when dealing with  random text or calls from unknown numbers. Just recently, i had to help convinced my friend on not actually sending money to a potential scammer promising him alot and a job offer but first he had to pay for reservations on spot in the company.  It took me some time to finally convinced him. They many scammers and hackers out there so we should all be careful

Apart from the fact that the PDF file itself has a bad reputation, I don't understand how to send it to your phone. I literally broke my head trying to add some files to my phone in the SMS messages section. You can add a link to a file easily, but I couldn't add the file itself. Does Android allow sending files via SMS? There is also a blacklist for blocking unknown numbers; isn't this in Android? In any case, to avoid the temptation to open the file, remove the program from your phone that allows you to open PDF files.

But if you are constantly receiving such messages by email, maybe change your email?

I don't know the type of android phone you have but yes android phones allow sending files through messages ( MMS aka MultiMedia Messaging Service )  , if it's not working on your phone you might want to adjust some settings under messages.

I guess it's not only her phone. Although mine allows me to send some Media file like video, music, picture but there's no option to send PDF. And I have tried to temper with my settings and it's still not working. Since I'm unable to send PDF file through SMS will I be able to receive them? I'm just asking so as to know if I should be concerned with this update or not.

All types of android (afaik) have built-in message filters in their settings. But I don't really think it can completely prevent that if hackers use online SMS services.

As long as it contains a link, it is very possible to insert something malicious that isn't realized especially mobile devices that are known to have operational limitations such as previewing links. I've seen a tutor somewhere that you can find out someone's location accurately just by sending someone a photo. Hackers might be able to do something crazier, maybe some kind of confirmation router with just a link. idk

The problem there is he download a file without knowing the content. And this is really a big problem to those people who's innocent about such doing so hope this serves as a lesson for people to be more cautious on links they are seeing and never click anything online specially downloading any files which is unfamiliar to us since this is how hacking or any related incident starts.

Probably you're using a custom app for your messages, either from the manufacturer or the carrier, and the file menu is probably hidden somewhere. This is how it looks on my work phone with both the normal sms options and the Samsung one side by side:
https://talkimg.com/images/2023/05/20/blob53914aa7533344ed.jpeg


Don't you have send file option? That's what I used to select a pdf file.

Anyhow, it doesn't really matter on the subject as these spammers are not using their phones to manually send those links but automated services.

Yes, I meant SMS and sending a PDF file. But I understand that MMS can do this, but it will also be a little problematic with PDF files. To do this, as described, it is necessary to rename this file to an extension for photos or drawings.
And you are right that scammers probably do not use their phones to send such files, but use mass mailing services with fake or purchased phone numbers.
I was interested in the fact that someone could send an SMS with files, as I also receive a lot of spam and advertisements with links, but fortunately, I did not have to receive direct file sends.
Thanks, OP, for letting know about this scam.

https://tech25s.com/how-to-send-a-pdf-file-in-a-text-message-a-few-methods/

Perhaps the hacker can extract phone data, but how can he make bank transfers without his identity being discovered? op mentioned that the cases he found are all in Nigeria or that hackers are targeting Nigerian users. Is transferring money through bank accounts easy to this degree there? I find this rather strange.
Honestly, I did not know before reading this topic that pdf files can be sent via SMS. I researched a little bit about it and discovered that this is actually possible. Therefore, there is a possibility of hacking using it.

Even though something like this has never happened to me, several similar attempts have been sent on Telegram and email and other chat applications.
In fact I really need to be aware of how highly it is possible for us to get hacked and have our data and assets stolen by them, and this makes me believe that not downloading automatically will prevent things we don't want.

Having this preference in every chat media is important for security, and if one of you doesn't have it yet, do it before it's too late.

indah rezqi, obviously that is good security advice that everyone should practice. That will prevent you from automatically downloading any files regardless of whether they are from private chats or group chats. If it's from someone you know, then it's probably safe for you to get it but the risk is they don't know what they're sharing with you is a virus or malware.

I have had this preference for a long time and keep track of changes regularly. This is a way of minimizing the security risk of malicious files. Regular checkup and regular virus scans can also help, but not automatically downloading any media is the first step.

We don't yet know how the virus works and always sends messages with hidden numbers, but you are right that we have to increase security protection on our devices, if you have a PC device or other smartphone then the solution is safer to move important data to another device to temporarily to avoid hacking of banks and assets from blockchain wallets.

I don't know about new types of virus attacks and some of the suggestions above need to be improved for routine anti-virus scanning to prevent virus files from entering chat telegrams or emails.

Can't the cellphone number be blocked? If you can, just block the cellphone number.
because fraud like that is very detrimental, I also sometimes receive strange messages on my cell phone, but strangely the messages are like I am sending them to other people even though I didn't send any messages.
should be more careful.

I was reading a few topics and came across this discussion and I remembered my experience last week.
I am also one of those people who receive messages via a chat and telephone application on my cell phone.

This January I have received 2 consecutive messages from unknown numbers.
First I received a message from an unknown number and it had a phone code +504 which was clearly different from the phone code of my country.
Secondly I got messages on behalf of a local bank from my country, but even I never had savings or an account at that bank.
When the message came in I only saw it from my cellphone notification, not until I opened the message.
I glanced at my phone's notifications, both messages included a link as well.

Even though I immediately deleted it after that, to be honest I'm still worried about hacking the cellphone.

Hacker must have hidden the virus in the pdf using steganography which is why attachments sent to me from any unknown email addresses I don't bother opening such.. Be it image, mp3, exe all these go straight to the trash can no compromise !!

Sorry for your friends loss. Why do I get the feeling that your neighbor could actually have saved his private key on the same device which made it easy to steal his coins or its one of those phishing emails that say your mew needs to be verified and when you proceed with this you hand over your keys to the hacker on a silver plate.

Yes it does..
https://i.imgur.com/rR715i1.jpg
The attachment option allows you to send any kind of file that's supported by your device, be it an image, a doc, an Excel spreadsheet, a PDF, etc.

Address poisoning doesn't make anyone do anything. It's a scheme those who aren't properly using cryptocurrency wallets fall for because of ignorance and laziness. I don't think it's going to happen any longer on Tron after their most recent network upgrade. Not sure what BSC is going to do about it. Transactions now cost more to broadcast especially smart contract interactions. Scammers will now have to pay significantly more for their 0-value transactions, which will get rid of 90% of them.

Or you can do the even easier thing and not download and open weird PDFs due to your curiosity. Curiosity killed the cat. Remember that.

OP said it was a hidden number. You can't block it if it's hidden. However, you can block all hidden numbers. Sometimes people or institutions call from hidden numbers. With that feature activated, you wouldn't get those calls either.   

So once you click on it, you get the virus no matter what?  So iphone as well or only android?


But if you click on it, does it auto open the pdf?  So all your emails would get compromised?


But how does it do anything with online banking?  So it does an unauthorized transfer?  But you contact your bank and say it is fraud and you get your money back right?

Why do people download PDF files from unknown sources? For the sake of security, individuals should not open any phone messages and emails sent from strange numbers and emails from unknown addresses. Malware and phishing frauds are on the rise right now, and we ought to be aware of that. Mobile phones already have a feature similar to that of emails that automatically moves unknown messages to the spam folder. If not, contact the authorities because they have the authority to conduct a more in-depth investigation into the matter and may be able to apprehend the perpetrators.

The fact alone that I didn't do anything that requires I download a pdf file is a red flag to me. These hackers get innovative and crafty when trying to scam people but this is quite boggling. Too bad someone had to be naive enough to lose such a huge amount; but it just goes to prove the necessity of protecting your phone from such attacks by not being quick to open messages from unknown senders, especially a weird one at that.

I have received such on countless occasions, but I know that once I don't see the number it was sent from, it is probably spam or hackers.
Generally, if the senders address of a received text message or email message isn't familiar or not clear, it shouldn't even be opened or read. It should be marked as spam on your device and deleted. It will eventually stop when you ignore.

These things keep happening...
I've been receiving several SMS,MMS, MAILS etc, from unknown sources which I can't either give a feedback or respond to their text, tweet whatsoever.. I'll simply ignore that whenever I see it.
Sometimes, there'll pop up on your device when you're browsing through the net and you won't be given an option to clear, delete, back off or escape... sometimes you'll be left with no other option but to close that particular tab. These guys keep inventing different strategies to clone people's bank account/wallets...we just have to watch out for them.

Sandra 🧑‍🦰

This is a sad one and this very scam has been in use for a long time now and recently I was also scammed on an exchange through some phishing link and that is another typical lesson for me in the world of cryptocurrency and I hope we also all learn from this lesson.
I'm so sorry about that and he should next time try using a 2 factor verification for more security because alot is going on with the internet and nothing is guaranteed here.

I've never heard of this method so I guess am 1 of the many persons this information should be useful to.
Although on several occasions I've heard of shared links on social media platforms.
 I really do wonder what scammers really want, like, why not just use the energy to get a more profitable, admirable and valuable job other than ruining and taking advantage of people.