I have tried several times and I cannot see where in the community wiki page on Boot Repair that there is a link to a 32 bit ISO image that has a Linux kernel with the Intel SPI bug. I used to have permission to edit community Wiki pages. I do not have that permission any more but to place a warning on that page or to remove a link to an ISO image download site a person would need to know specifically the line in the instructions that need to be edited. You do not give this information.
As regards the bug in the Linux kernel a fix has been in place since the second week of December 2017. The fix was made within days of the bug being reported. Besides which the only version of Ubuntu that may have the buggy kernel is Xenial = 16.04 and that would have had several Kernel updates since 2017.
This bug was reported yesterday against boot repair and I cannot understand why. The person who reported the bug failed to add any comments. As far as I know Boot Repair does not install Linux kernels. A typical Boot Repair repair would be to reinstall the Grub boot loader. There is an option to "Purge kernels then reinstall last kernel (beta)". I do not know how that works. It may download the kernel from a Ubuntu site. In which case the replacement kernel would have been patched with the bug fix.
Ubuntu developers have stopped providing 32 bit versions of Ubuntu. Any ISO image built after 22/12/2017 would have a patched kernel. Or a newer kernel that does not have the bug. Any ISO image with the 4.14 kernel would not have had this bug in the Linux kernel.
Regards