static void vbe_update_vgaregs(VGACommonState *s)
{
    int h, shift_control;

    if (!vbe_enabled(s)) {
        /* vbe is turned off -- nothing to do */
        return;
    }

    /* graphic mode + memory map 1 */
    s->gr[VGA_GFX_MISC] = (s->gr[VGA_GFX_MISC] & ~0x0c) | 0x04 |
        VGA_GR06_GRAPHICS_MODE;
    s->cr[VGA_CRTC_MODE] |= 3; /* no CGA modes */
    s->cr[VGA_CRTC_OFFSET] = s->vbe_line_offset >> 3;
    /* width */
    s->cr[VGA_CRTC_H_DISP] =
        (s->vbe_regs[VBE_DISPI_INDEX_XRES] >> 3) - 1;
    /* height (only meaningful if < 1024) */
    h = s->vbe_regs[VBE_DISPI_INDEX_YRES] - 1;
    s->cr[VGA_CRTC_V_DISP_END] = h;
    s->cr[VGA_CRTC_OVERFLOW] = (s->cr[VGA_CRTC_OVERFLOW] & ~0x42) |
        ((h >> 7) & 0x02) | ((h >> 3) & 0x40);
    /* line compare to 1023 */
    s->cr[VGA_CRTC_LINE_COMPARE] = 0xff;
    s->cr[VGA_CRTC_OVERFLOW] |= 0x10;
    s->cr[VGA_CRTC_MAX_SCAN] |= 0x40;

    if (s->vbe_regs[VBE_DISPI_INDEX_BPP] == 4) {
        shift_control = 0;
        s->sr_vbe[VGA_SEQ_CLOCK_MODE] &= ~8; /* no double line */
    } else {
        shift_control = 2;
        /* set chain 4 mode */
        s->sr_vbe[VGA_SEQ_MEMORY_MODE] |= VGA_SR04_CHN_4M;
        /* activate all planes */
        s->sr_vbe[VGA_SEQ_PLANE_WRITE] |= VGA_SR02_ALL_PLANES;
    }
    s->gr[VGA_GFX_MODE] = (s->gr[VGA_GFX_MODE] & ~0x60) |
        (shift_control << 5);
    s->cr[VGA_CRTC_MAX_SCAN] &= ~0x9f; /* no double scan */
}

The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.