void ArthurOutputDev::updateStrokeColor(GfxState *state)
{
  GfxRGB rgb;
  QColor penColour = m_currentPen.color();
  state->getStrokeRGB(&rgb);
  penColour.setRgbF(colToDbl(rgb.r), colToDbl(rgb.g), colToDbl(rgb.b), penColour.alphaF());
  m_currentPen.setColor(penColour);
  m_painter->setPen(m_currentPen);
}

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