Dangerous Stranger: Internet sharing and the loss of valuable data

  • The trend related to sharing information about oneself is developing dynamically and today it affects almost everyone. Only 7% of people do not share such information digitally.
  • People who share their data are more likely to suffer from data loss than those who protect it. Of those who share it, almost half have experienced data loss on their smartphones (47%) and computers (52%), and 20% have lost data on tablets. When it comes to people who do not share their data at all, only a few of them lost data – 13% related to smartphones, 23% to computers, and 4% to tablets.
  • People who share data about themselves put themselves at greater risk from device performance issues – 37% of people who don’t share information about themselves admitted having problems with their smartphone. This result was 71% for people who shared any of their data. These problems were related to the display of intrusive advertisements (51%), redirects to other sites (33%), changing settings without the owner’s consent (17%), or infection with malicious programs (14%).
  • As data sharing is very popular, there is no point in calling for an end to sharing your digital information. On the other hand, it is worth encouraging your users to share responsibly with people they trust. For example, according to our study, 44% of people share their information publicly, and one in five admitted to sharing even sensitive and private information with strangers.
  • Despite the fact that sharing information with strangers is more dangerous, those who do so are more likely to experience data loss and device problems. 59% of users who shared something with strangers lost data on their smartphones (compared to 41% of people who did not share anything with strangers) and 78% had problems with their smartphones (compared to 67% for people who did not. ).
  • What’s more, we share not only data, but also devices containing our valuable data. Many people hand their devices to others, share PINs and passwords, allowing access to their digital life. For example, one in five (22%) people have left their devices unblocked and unattended when other people are around, and nearly a quarter (23%) have lent their devices to someone else from time to time.
  • Users who practice this risky behavior are also twice as likely to experience data loss. For example, only 34% of people who avoid risky behavior in relation to smartphones have lost the data stored on them – compared to 65% of people who like to risk it this way.


Today, people use their devices to store data on all aspects of their digital lives – from photos to contact information so that they can stay in touch with their loved ones. This data is valuable and losing it can be really painful (for more information, see the Pain after losing valuable data report ).

Moreover, the growing amount of valuable data, along with the applications we use to store and access this data, is increasing digital clutter (for more information, see the Digital Clutter and Its Risks report ), which can potentially expose users to danger.

Despite the potential dangers of our digital life, sharing information has never been easier, and we’ve never wanted it more. We share photos of ourselves, our travels, family, friends and children with others. Who can blame us? Sharing helps us forward messages or keep you in touch over long distances.

What if we share too much information? What does it threaten?

To help users protect their valuable data, Kaspersky Lab has conducted a study on sharing habits. The results raised a lot of concern for us: it turned out that we share too much data with people who are completely alien to us, which is dangerous.

The report includes the results of the survey and information to make people think before sharing something. Because sharing isn’t always associated with caring.


The study uses the conclusions of an online survey conducted by the research company Toluna and Kaspersky Lab in January 2017. The study assessed the attitudes of 16,250 users aged over 16, from 17 countries. Data have been weighted globally to be representative and consistent, and split equally between men and women.

Our data in the hands of strangers

The trend of sharing information about us is growing and affects almost every person. According to our study, only 7% of people do not share information with others.

As data sharing is very popular, there is no point in calling for an end to sharing your digital information. On the other hand, it is worth encouraging your users to share responsibly with people they trust. For example, according to our study, 44% of people share their information publicly, and one in five admitted to sharing even sensitive and private information with strangers.

Many people have heard from an early age that you must not talk too much about yourself to strangers. And while we are familiar with the statement that an alien can be dangerous, we are happy to share information about our digital life with those we do not know.

What data are we talking about?

We most often share photos, with the majority (91%) sharing them via the Internet. Meanwhile, 55% of respondents admitted that they shared some of their documents, and 55% shared selected messages with others.

Simply put, users share too much over the internet, potentially exposing themselves to unnecessary threats. Overall, one third of respondents (30%) share passwords on the Internet, which may, for example, lead to a situation in which someone will gain access to someone else’s digital life.

Irresponsible sharing is nothing new: for example, last year we conducted an experiment to  study the relationship between users and their devices. It turned out that although people love their devices and the data stored on them, as many as 97% of them willingly give someone the PIN code for the device upon request (in this case, our researchers asked for the code). It was enough to ensure that we needed it that the respondents would without hesitation provide us with their devices containing all the data – no matter how valuable they were.

Such sharing of passwords and PINs can be a risky behavior as it allows others to gain access to information about us that should be protected. Our research also shows that, similar to the sharing of passwords, people risk identity theft or financial attack by sharing financial and payment-related details (37%) and scans of passports, driving licenses and other personal documents (41%).

Share memories and valuable data

Memories in the form of private and sensitive photos of oneself and others are the most important among the data provided. This is interesting because people’s memories are among the most valuable data stored on devices that can connect to the Internet. When we asked the respondents what data was most important to them, the most common answer was „private and sensitive photos and videos with me” (49%). This item also came first in terms of the most severe loss.

The most personal types of data also included „photos and videos of my children” and „private and sensitive photos and videos of other people (such as my partner)”. But despite the importance attached to them, users willingly give this data to others: more than half share private and sensitive photos and videos with themselves (54%), 70% share photos and videos with their children, and 45% share private and sensitive videos and photos other people.

Young people share more willingly

Young people are more willing to share data with other people. 61% of the respondents aged 16-24 and 64% of those aged 25-34 share private and sensitive photos of themselves with other people, while in the age group over 55 the proportion was 38%. Two-fifths of young people also share their financial and payment details (42% in many 16-24 and 46% aged 25-34). The group of people over 55 who do this is 27%.

It is interesting that people in the 25-34 age group are more likely to share data than those in the 16-24 age group. It is possible that people aged 25-34 have never had a chance to effectively educate themselves about the dangers of sharing information on the Internet, while the younger group, the „Generation Z”, grows up surrounded by new technologies, which automatically increases awareness of this range.

The Japanese take care of their belongings, the Russians give up too much

Russian respondents share private and sensitive photos and videos more often than users in other countries, and the Japanese are least likely to do so. For example, three-quarters of Russians (74%) share private and sensitive photos and videos with their participation, compared to a quarter (24%) of Japanese.

Overall, when it comes to memories, 87% of respondents share photos and videos of their travels. Posting this type of memoirs is popular especially in Israel (92%), the United Arab Emirates (95%), the Asia-Pacific region (95%) and Latin America (92%), but far fewer users share their travel memories in Japan ( 48%).

People in the United States and the Asia-Pacific region are most likely to share data with strangers (30% and 28%, respectively), and also share data with the public more often than other countries (except private photos and videos in Russia). Japan opposes this trend and does not share data with outsiders (8%).

Common problem?

According to our study, there is an interesting relationship between the number of people sharing more information online and the number of people who have had a data loss event.

Among those who do not share information at all, only 13% have experienced data loss on their smartphone, 4% have lost data on their tablet, and less than a quarter (23%) have lost data on their computer.

For people who share data with others, the percentage of data loss is much higher: almost half have lost data on smartphones (47%), computers (52%) and tablets (20%).

Device problems

This relationship has also emerged between those who share data and those who have had problems with their devices. For example, only 37% of people who didn’t share their information experienced some sort of problem with their smartphone. When it comes to people who publish some information, the percentage also increases to 71%.

The most common smartphone issues reported by people sharing their data include intrusive advertising (51%) and battery life issues (41%). Much worse problems were also reported: for example, 14% of smartphone users sharing data fell victim to a malicious program, and 19% found an application running on the device without their awareness.

However, device problems are more common on the computers of those who share their data – 83% of them had computer problems, 28% had problems with a malware, and 28% found applications on their hardware that they did not know about.

Dangerous stranger

Among all interviewees, those who shared with strangers most often lost data and had problems with the device.

59% of users who shared data with strangers lost data on their smartphones (compared to 41% of those who did not share data with strangers) and 78% had problems with a smartphone (compared to 67% who did not share information with strangers).

Unfortunately, there was a link between sharing data with strangers and the occurrence of data troubles. This conclusion should make people consider who they share their information with and whether they run the risk of sharing information with strangers.

Can you hold it for a while?

The study shows that people are sharing not only data but also devices, potentially compromising valuable data stored on them. Many people have admitted having experienced „risky sharing” – for example, giving a device to a stranger or sharing a PIN or password.

This is all the more surprising because, according to our study, people value their devices very much. For example, its loss or theft has been rated as the second most stressful event in many regions (after a family member’s illness). So if devices and their data are so important – and so painful to lose them – why are users sharing them in a way that exposes them to threats?

Trust a stranger

It’s surprisingly common for people to trust others – in some cases even complete strangers – when it comes to devices. 43% admitted giving their phone or tablet to a stranger to take a photo of them, 32% said they gave the device to make a call, and one in five people (18%) gave the device to someone to search for something on the Internet. In these cases, users not only physically give their devices to strangers, but also trust strangers with all personal and sensitive information that resides on the hardware.

Men are more generous than women when it comes to lending their device to strangers: one in three (36%) admitted having borrowed a device to make a call; meanwhile, every fourth woman (28%) decided to take such a step.

Friends and family first

Young people are more generous than older people when it comes to sharing tablets and smartphones with their family. Two-thirds of young people (67% aged 16-24 and 62% aged 25-34) lent their device to a family member temporarily, but this figure is lower for older people (49% for those aged 45-34). 54 and 34% among respondents over 55). Japanese people are least likely to give away their device to a family member for a while (27%), compared to 71% in the UAE.

The same pattern occurs when it comes to users who share their passwords or PINs with a family member so that they can use a tablet or smartphone. Here, too, people in the younger category more often admitted to doing so (42%) than people aged over 55 (20%). This is most often done by respondents in the UAE (42%), and the least often by the Japanese (10%).

This pattern goes beyond the family and also includes friends. Respondents aged 16-24 are more likely to share their PIN or graphic password with friends in order to gain access to the device – one in three people (35%) admitted this. This result drops to 25% for the age of 25-34 and only 4% for the age over 55.

Overall, 72% of people take the risk of borrowing their smartphone or tablet. Respondents from Japan (46%), Iberia (65%) and Europe (66%) are less exposed to such a risk. 70% of people in the United States, 81% in Israel, 82% in the UAE and 80% in the Asia-Pacific region admitted having „risked sharing”.

Knowingly compromising valuable data

People seem to be relatively realistic about the security of their devices. 47% of respondents are aware that their own careless behavior and risky sharing can cause security issues, and only 9% believe that their smartphone is the safest place for data. Nevertheless, as seen above, this awareness does not go hand in hand with appropriate behavior. People are happy to hand their devices to others (strangers and family), share passwords, and even leave their devices unlocked and unattended among others.

What kind of threat are we talking about? Well, other users can, for example, change the device settings and use them as if their owners do not necessarily want to. Malicious activity is not always the reason – a family member with the best intentions might accidentally download a malicious program onto a device that puts data at risk. In turn, a stranger could cause damage to the device on purpose.

Risk without reward

Worse still, people who engage in such risky activities lose data twice as often.

For example, 65% of people who carried out a risky activity on their smartphone (e.g. lent their device to strangers) also lost data on their smartphone. The percentage of people who did not take such a step was 34%. When it comes to tablets, 52% of users who acted risky lost data on their device, and 19% of those who did not take such a step.

Risky device problems

People who behave recklessly lose not only their – potentially valuable – data, but also have problems with their devices. The majority (91%) of such people have taken part in risky activities on their smartphones and have had problems with the device, and this percentage rises to 73% for more cautious people.

This pattern also works for tablet users. Those who exposed them to a dangerous situation had more likely to be changed settings without their knowledge (23%) than more cautious users (11%) and had a greater chance of being redirected to unwanted sites (44%) than more cautious users (26 %). They, too, were twice as likely to be attacked by malicious programs (21% to 10%).


This report shows that while people love their data, they are constantly putting it at risk by sharing it online or by taking risky activities such as sharing their smartphones or tablets with others.

We have more and more data shared; Only 7% of users do not participate in it. However, as the study has shown, this is often valuable human data – such as memories made up of photos and videos of them – and is shared most often. Moreover, this data is not always shared only with close friends or family, but is also available for public use.

People are literally handing out their precious data to others. They do it willingly and do not do it in private. This is a massive trend.

But the study in question also highlighted the fact that those who share their data more voluminously are also more likely to experience data loss or have problems with their devices.

Kaspersky Lab tries to encourage users to protect what matters most to them – no matter how and to whom they share their digital life. Since data sharing is so popular, we know it is not wise to persuade people to stop. However, we encourage you to think twice with whom we share our data and how much we make it public – after all, those who share a lot of information with strangers suffer the most from data loss or device problems. We also encourage all internet users to pay more attention to ways to secure their data and protect their privacy before their devices or data fall into the wrong hands.