Incomplete sanitization of SVG files allows to embed other images into previews
Package
Server
(Nextcloud)
Affected versions
>= 27.0.0, >= 28.0.0, >= 29.0.0
Patched versions
27.1.10, 28.0.6, 29.0.1
Server
(Nextcloud Enterprise)
>= 24.0.0, >= 25.0.0, >= 26.0.0, >= 27.0.0, >= 28.0.0, >= 29.0.0
24.0.12.15, 25.0.13.10, 26.0.13.4, 27.1.10, 28.0.6, 29.0.1
Impact
After an admin enables the default-disabled SVG preview provider, a malicious user could upload a manipulated SVG file referencing paths. If the file would exist the preview of the SVG would preview the other file instead.
Patches
It is recommended that the Nextcloud Server is upgraded to 27.1.10, 28.0.6 or 29.0.1
It is recommended that the Nextcloud Enterprise Server is upgraded to 24.0.12.15, 25.0.13.10, 26.0.13.4, 27.1.10, 28.0.6 or 29.0.1
Workarounds
References
For more information
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