void CairoOutputDev::setDefaultCTM(double *ctm) {
  cairo_matrix_t matrix;
  matrix.xx = ctm[0];
  matrix.yx = ctm[1];
  matrix.xy = ctm[2];
  matrix.yy = ctm[3];
  matrix.x0 = ctm[4];
  matrix.y0 = ctm[5];

  cairo_transform (cairo, &matrix);
  if (cairo_shape)
      cairo_transform (cairo_shape, &matrix);

  OutputDev::setDefaultCTM(ctm);
}

This weakness involves numeric computation errors, such as integer overflows, underflows, or precision losses, which can lead to miscalculations and exploitable behaviors in software.