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Firefox flags MP4 file as malware

  • 1 reply
  • 4 have this problem
  • 444 views
  • Last reply by cor-el

jordanf
jordanf

Hi,

Is there any reason firefox would flag an mp4 file legitimately?

  • The file extension and file type are absolutely mp4.
  • There seem to be no mp4 related zero days.

Does Firefox perhaps just treat all downloads from suspicious domains as malware? Is there a zero day I missed? Is this based on some missing metadata on the file or something?

Thanks for any advice you can give here, I'm scared.

Hi, Is there any reason firefox would flag an mp4 file legitimately? * The file extension and file type are absolutely mp4. * There seem to be no mp4 related zero days. Does Firefox perhaps just treat all downloads from suspicious domains as malware? Is there a zero day I missed? Is this based on some missing metadata on the file or something? Thanks for any advice you can give here, I'm scared.

Chosen solution

Yes, if a domain is flagged as a suspicious download location then all files downloaded from this location will be flagged, so this has nothing to do with the file extension. See also the about:url-classifier page.

Read this answer in context 👍 5

All Replies (1)

cor-el
cor-el
  • Moderator

Chosen Solution

Yes, if a domain is flagged as a suspicious download location then all files downloaded from this location will be flagged, so this has nothing to do with the file extension. See also the about:url-classifier page.