Telegram Messanger. Sergei Konkov / Getty

If a file titled "article_in_wsj.jpg" looks like a it might be an image file, criminals might be able to trick you into clicking a nasty link through the messaging app, Telegram. A file name processing glitch already being exploited in the wild makes it easy to make one file type seem like another.

In the wild: Researchers at the Kaspersky Lab noticed that Telegram did not check to make sure the app does not reverse the file type and found several instances of the issue dating back to March of last year. Their findings included cryptocurrency mining malware and opening backdoors into systems. The trick seemed to be popular for Russian criminals. Telegram has since patched the vulnerability.

How it works : To allow filenames in languages that read from right to left, Telegram recognizes a formatting marker called a right-to-left override (RLO) character. Any text after a RLO is displayed from right to left. Flip the right letters in "123gpj.js" and you get "1234sj.jpg," turning an potentially malware-hiding javascript (.js) file into what looks like an jpeg image.

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Robert Mueller speaks out on Roger Stone commutation

Former Special Counsel Robert Mueller testifies before the House Permanent Select Committee on Intelligence on Capitol Hill on Wednesday July 24, 2019. Photo: The Washington Post / Contributor

Former special counsel Robert Mueller responded to claims from President Trump and his allies that Roger Stone was a "victim" in the Justice Department's investigation into Russian interference in the 2016 election, writing in a Washington Post op-ed published Saturday: "He remains a convicted felon, and rightly so."

Why it matters: The rare public comments by Mueller come on the heels of President Trump's move to commute the sentence of his longtime associate, who was sentenced in February to 40 months in prison for crimes stemming from the Russia investigation. The controversial decision brought an abrupt end to the possibility of Stone spending time behind bars.

Trump dons face mask during Walter Reed visit

Trump wearing a face mask in Walter Reed National Military Medical Center on July 11. Photo: Alex Edelman/AFP via Getty Images

President Trump wore a face mask during his Saturday visit to Walter Reed National Military Medical Center, according to AP.

Why it matters: This is the first known occasion the president has appeared publicly with a facial covering as recommended by health officials since the coronavirus pandemic began, AP writes.

Updated 10 hours ago - Politics & Policy

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Illustration: Sarah Grillo/Axios

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