UP to three in ten resold mobile phones on second-hand sites are at risk of being hacked, a new investigation has revealed.

While people might think that sending an old phone to be recycled is a positive sustainable solution, a new study claims as many as one in three of them put on sale on second hand retailer sites could be insecure and this is not made clear to potential buyers.

The probe by Which? found that some two in three say they think a mobile phone is broken down for parts when sent for recycling, but the consumer organisation found that most phones are actually refurbished and resold.

Now one reseller, Music Magpie has said it will remove unsupported devices that were found to be on sale. It also said that going forward, it will provide information to consumers if a product is no longer receiving security updates.

It said that vulnerable mobile phone models on sale are the result of them no longer being supported by security updates.

The issue is that many phones will lose vital software updates after a certain amount of time and in as little as two years for Android phones.

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"From an environmental perspective, the longer a mobile phone remains in use, the better. But without security updates, our mobile phones become a perfect target for cybercriminals," said Jade Juilien of Which?

HeraldScotland:

"Ultimately, Android manufacturers need to commit to supporting their phones for longer than the average two to three-year period. That’s the only way to avoid people being forced to walk a tightrope between potentially putting others at risk or having their phone unnecessarily end up in landfill."

The consumer organisation examined the listings of three popular mobile phone recycling websites and found all were reselling mobile phones that, unknown to customers, are vulnerable to hackers.

Some of the phones being resold that were no longer receiving security updates include the Apple iPhone 5, Google Pixel XL, Huawei P10, Samsung A8 Plus (2018) and the Samsung Galaxy S7.

Which? found that 31% of mobile phone models on sale at second-hand goods chain CeX could be vulnerable because they are no longer supported by security updates.

This also applied to a fifth of the models found on Music Magpie and one in six on SmartFoneStore. Both told Which? that these only accounted for a very small percentage of sales.

SmartFoneStore also issued an update, adding a warning on unsupported devices so consumers are aware before they buy them. CeX did not provide a comment.

HeraldScotland:

Which? says that recently out-of-support devices might not immediately have problems, but without security updates, the risk to the user of being hacked is increased. Generally speaking, the older the phone, the greater the risk.

It said that until manufacturers offer complete transparency about how long devices will be supported, and those offering only a couple of years of support do better, it is more difficult to take advantage of the recycling services without putting consumers at risk.

Kate Bevan, Which? computing editor, said: “Keeping mobile phones in circulation for longer is better for the environment but it shouldn’t come at the cost of customer security. Unless manufacturers become more transparent, and those offering vital updates for only a couple of years do better, there is a risk that second-hand phones will be vulnerable to hackers or end up dumped in a landfill site.

“If your mobile phone is no longer receiving security updates you should consider upgrading as soon as possible. While you continue to use an out-of-support device, you must take steps to mitigate the risks – including using mobile antivirus software, managing app permissions and only downloading from official stores.”

Music Magpie said it refurbishes 95% of the products it receives from consumers, all of which are resold in the UK. It sells more than 250,000 phones a year.

HeraldScotland:

Music Magpie said it believed the issues was "an important matter across the industry" and added: “While we thoroughly look into it, we have made the decision to remove all of the stated devices from our store. These devices account for less than 1% of our stock and less than 1% of our sales, so while not a significant number, we still want to ensure we provide the correct messaging and advice to customers where these devices are listed, so that they can then make a better-informed decision on their purchase.”