WriteOnePNGImage() from coders/png.c (the PNG coder) has a for loop with an improper exit condition that can allow an out-of-bounds READ via heap-buffer-overflow. This occurs because it is possible for the colormap to have less than 256 valid values but the loop condition will loop 256 times, attempting to pass invalid colormap data to the event logger. The patch replaces the hardcoded 256 value with a call to MagickMin() to ensure the proper value is used. This could impact application availability when a specially crafted input file is processed by ImageMagick. This flaw affects ImageMagick versions prior to 7.0.8-68.

In CatromWeights(), MeshInterpolate(), InterpolatePixelChannel(), InterpolatePixelChannels(), and InterpolatePixelInfo(), which are all functions in /MagickCore/pixel.c, there were multiple unconstrained pixel offset calculations which were being used with the floor() function. These calculations produced undefined behavior in the form of out-of-range and integer overflows, as identified by UndefinedBehaviorSanitizer. These instances of undefined behavior could be triggered by an attacker who is able to supply a crafted input file to be processed by ImageMagick. These issues could impact application availability or potentially cause other problems related to undefined behavior. This flaw affects ImageMagick versions prior to 7.0.9-0.

A flaw was found in ImageMagick in MagickCore/colorspace-private.h and MagickCore/quantum.h. An attacker who submits a crafted file that is processed by ImageMagick could trigger undefined behavior in the form of values outside the range of type `unsigned char` and math division by zero. This would most likely lead to an impact to application availability, but could potentially cause other problems related to undefined behavior. This flaw affects ImageMagick versions prior to 7.0.8-68.

In IntensityCompare() of /magick/quantize.c, there are calls to PixelPacketIntensity() which could return overflowed values to the caller when ImageMagick processes a crafted input file. To mitigate this, the patch introduces and uses the ConstrainPixelIntensity() function, which forces the pixel intensities to be within the proper bounds in the event of an overflow. This flaw affects ImageMagick versions prior to 6.9.10-69 and 7.0.8-69.

A flaw was found in ImageMagick in MagickCore/quantum-export.c. An attacker who submits a crafted file that is processed by ImageMagick could trigger undefined behavior in the form of values outside the range of type `unsigned long long` as well as a shift exponent that is too large for 64-bit type. This would most likely lead to an impact to application availability, but could potentially cause other problems related to undefined behavior. This flaw affects ImageMagick versions prior to 7.0.9-0.

There are several memory leaks in the MIFF coder in /coders/miff.c due to improper image depth values, which can be triggered by a specially crafted input file. These leaks could potentially lead to an impact to application availability or cause a denial of service. It was originally reported that the issues were in `AcquireMagickMemory()` because that is where LeakSanitizer detected the leaks, but the patch resolves issues in the MIFF coder, which incorrectly handles data being passed to `AcquireMagickMemory()`. This flaw affects ImageMagick versions prior to 7.0.9-0.

In WriteOnePNGImage() of the PNG coder at coders/png.c, an improper call to AcquireVirtualMemory() and memset() allows for an out-of-bounds write later when PopShortPixel() from MagickCore/quantum-private.h is called. The patch fixes the calls by adding 256 to rowbytes. An attacker who is able to supply a specially crafted image could affect availability with a low impact to data integrity. This flaw affects ImageMagick versions prior to 6.9.10-68 and 7.0.8-68.

The PALM image coder at coders/palm.c makes an improper call to AcquireQuantumMemory() in routine WritePALMImage() because it needs to be offset by 256. This can cause a out-of-bounds read later on in the routine. The patch adds 256 to bytes_per_row in the call to AcquireQuantumMemory(). This could cause impact to reliability. This flaw affects ImageMagick versions prior to 7.0.8-68.

TIFFGetProfiles() in /coders/tiff.c calls strstr() which causes a large out-of-bounds read when it searches for `"dc:format=\"image/dng\"` within `profile` due to improper string handling, when a crafted input file is provided to ImageMagick. The patch uses a StringInfo type instead of a raw C string to remedy this. This could cause an impact to availability of the application. This flaw affects ImageMagick versions prior to 7.0.9-0.

There are 4 places in HistogramCompare() in MagickCore/histogram.c where an integer overflow is possible during simple math calculations. This occurs in the rgb values and `count` value for a color. The patch uses casts to `ssize_t` type for these calculations, instead of `int`. This flaw could impact application reliability in the event that ImageMagick processes a crafted input file. This flaw affects ImageMagick versions prior to 7.0.9-0.