#763 CVE-2026-25799

[Petr Gajdos]

It seems that GraphicsMagick suffers with the same problem as used to the ImageMagick codebase. On two places in yuv.c, there is:

     if ((horizontal_factor != 1) && (horizontal_factor != 2) &&
          (vertical_factor != 1) && (vertical_factor != 2))
        ThrowYUVReaderException(OptionError,UnsupportedSamplingFactor,
          image);

The condition is true only if both factors are wrong, which does not look to be intended.

[Bob Friesenhahn]

This issue is addressed by Mercurial changeset 18005:85f3971e259d, which is included in the latest (1.4.020260306) source development snapshot.

Much thanks to Petr, who tried extra hard to communicate about this issue with me.