diff --git a/tests/ImageSharp.Tests/Formats/Png/PngDecoderTests.Chunks.cs b/tests/ImageSharp.Tests/Formats/Png/PngDecoderTests.Chunks.cs index 823009b68d..a53bd1dd5c 100644 --- a/tests/ImageSharp.Tests/Formats/Png/PngDecoderTests.Chunks.cs +++ b/tests/ImageSharp.Tests/Formats/Png/PngDecoderTests.Chunks.cs @@ -161,6 +161,31 @@ public partial class PngDecoderTests using Image image = Image.Load(stream); } + [Fact] + public void Decode_tRnsChunk_WithAlphaLengthGreaterColorTableLength_ExceptionIsThrown() + { + byte[] payload = [137, 80, 78, 71, 13, 10, 26, 10, // PNG signature + 0, 0, 0, 13, // chunk length 13 bytes + 73, 72, 68, 82, // chunk type IHDR + 0, 0, 0, 1, 0, 0, 0, 1, 8, 3, 0, 0, 0, // data + 40, 203, 52, 187, // crc + 0, 0, 0, 6, // chunk length 6 bytes + 80, 76, 84, 69, // chunk type palettte + 255, 0, 0, 0, 255, 0, // data + 210, 135, 239, 113, // crc + 0, 0, 0, 18, // chunk length + 116, 82, 78, 83, // chunk type tRns + 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, // data + 0, 0, 0, 10, // chunk length + 73, 68, 65, 84, // chunk type data + 120, 156, 99, 96, 0, 0, 0, 2, 0, 1, 72, 175, 164, 113]; // alpha.Length > colorTable.Length + + using MemoryStream stream = new(payload); + InvalidImageContentException exception = Assert.Throws(() => Image.Load(stream)); + + Assert.Equal("The tRNS chunk contains more alpha values than there are palette entries.", exception.Message); + } + private static string GetChunkTypeName(uint value) { byte[] data = new byte[4];