ImageSharp is a 2D graphics library. From 4.0.0 until 4.1.2, ExrBaseDecompressor.UndoZipCompression accepts a nonempty ZIP or ZIPS inflate result that is shorter than the EXR block's required size. ZipExrCompression.Decompress reconstructs the returned prefix while ExrDecoderCore processes the full expected block from a buffer obtained through Configuration.Default, allowing bytes retained from a completed prior ImageSharp operation to appear in decoded pixels. Applications that expose pixels or output from the later attacker-controlled EXR decode can disclose process-local image data. This issue is fixed in version 4.1.2.
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