The Independent newspaper’s blogging platform has been compromised with malware that infects readers’ computers, according to security experts.
Researchers from Trend Micro found blogs on the website had been modified to install malware known as Cryptesla on readers’ devices.
The malware holds files on the host machine to ransom and demands a payment to restore them.
The Independent has not yet commented.
According to Trend Micro, the ransomware has been present on the Independent blogs website since at least 21 November.
“We reported it to them on Tuesday – but, as of today, it is still happening,” said Raimund Genes, chief technical officer at Trend Micro.
“Now we need to go public to warn people who are not using security software like ours.”
The malware exploits a security hole in Adobe Flash Player to install itself on a victim’s computer.
Once downloaded, it sets about encrypting documents, rendering them useless without the key to decrypt them, for which it demands a ransom.
The vulnerability in Flash has since been patched, but anybody using an old version of the web browser plug-in could still be at risk.
“For a while on Tuesday, the malware didn’t trigger. But that was not the Independent solving it, it was the attackers updating the malware with a new version,” said Mr Genes.
“My advice is to update your Flash Player. Always do it immediately when it says an update is available, because Flash remains one of the main ways attackers can compromise a system.”