According to Renckhoff, Case C‑161/17, rendered on 2018-08-07 (see also this summary on IPKat), this constitutes an unauthorized communication to the public. The case involved whether a re-upload of a photograph that was already made freely available by consent of the photographer is an infringement. Paragraph 28:
[...] In particular, the communication of a work by means not of a hyperlink, but by a new posting on a different website from that on which it was initially communicated with the consent of the copyright holder, should be treated as a ‘new communication to the public’, in particular, having regard to the fact that, as a result of the making available of the photograph once again, the copyright holder is no longer in a position to exercise his power of control over the initial communication of that work.
That the copyright holder must be able to exercise power of control over the initial communication was determined in Soulier & Doke, and as pointed out in the IPKat article, Renckhoff isn't really that big an extension on existing EU copyright case law.