Rufus developer here.
The problem is that, due to lack of timely releases, GRUB 2.06 has become a complete shit show, if you pardon my language, because what Ubuntu identifies as "GRUB 2.06" in Ubuntu 23.04 and what Ubuntu identifies as "GRUB 2.06" in Ubuntu 22.04 are actually two very different versions of the vanilla GRUB 2.06 source, with a bunch of completely different incompatible patches applied, since the Ubuntu folks, like everybody else, have understandably become annoyed at the lack of a GRUB release since 2.06, two years ago, and have taken it upon themselves to cherry pick important fixes and improvements from the upcoming version of GRUB to apply them to the one they use for Ubuntu ISOs.
Oh, and just to clarify, GRUB is the bootloader that displays the initial Ubuntu selection menu and ultimately produces the 452: Out of range pointer error you get...
The problem is that, to make a GRUB based media boot for BIOS/Legacy, Rufus needs to install a replacement for GRUB 2.06 (we can't get one from the ISO itself). But since the Ubuntu folks did not apply a version suffix to differentiate Ubuntu 22.04.2's GRUB 2.06 from Ubuntu 23.04's GRUB 2.06, we currently have no choice but to pick one GRUB 2.06, and unfortunately, the GRUB 2.06 that works for Ubuntu 23.04, which is what Rufus 4.0 uses, does produces a 452: out of range pointer when used with Ubuntu 22.04 and the GRUB 2.06 that works for Ubuntu 22.04, which is what Rufus 3.22 uses, produces a 452: out of range pointer when used with Ubuntu 23.04 (again, these GRUB 2.06, despite allegedly being the same version, are incompatible with one another). Rufus does have a solid mechanism to download specific versions of GRUB as needed (so that we can install one with specific patches when required), but that only works if distro maintainers do their job and clearly flag their GRUB version as something that is not vanilla, by adding a suffix to the version for instance...
I'm afraid that there is currently no easy solution to address this problem in Rufus, outside forcing people to use DD, which, despite what many appear to think, is not a good default, or asking people installing Ubuntu 22.04 to use Rufus 3.22 (which uses the old non Ubuntu 23.04 incompatible version of the GRUB 2.06 bootloader) and asking people installing Ubuntu 23.04 to use Rufus 4.0 for the time being.
You can download all these various versions of Rufus from https://rufus.ie/downloads/.
The best I might be able to accomplish in future versions of Rufus is to use a specific GRUB 2.06 according to the label of the ISO (since, despite my best effort, there is no easy way to spot difference we can leverage between the GRUB binaries embedded in the Ubuntu ISOs to identify which GRUB 2.06 should be used, and we have to do the same for Fedora, so we need something that works for more than Ubuntu anyway). However, this solution will require a lot of maintenance behind the scenes and will be imperfect.
All in all, it's users like you who are paying the price of GRUB maintainers thinking that they don't need to release in a timely manner (unfortunately this is not the first time this has happened, as we warned them that not doing so was already a major last time a serious GRUB vulnerability was found with regards to Secure Boot), as well as Ubuntu maintainers failing to understand that, when you do apply a bunch of patches to a source, you MUST alter the version string report and not pretend you are using the vanilla one. That is the real problem here, because if GRUB or Ubuntu had been doing any of the above, you, and tons of other people trying to install older versions of Ubuntu on Legacy systems using Rufus, wouldn't be in this mess...
UPDATE (2023.06.02):
Rufus 4.1 added a workaround that should make all versions of Ubuntu work again.
If you are still experiencing this issue:
- Please make sure that you use Rufus 4.1 or later.
- If you created a drive with Rufus in the past, try Alt-D to force Rufus to download the relevant GRUB bootloaders again.
- If this doesn't work and you are still getting the
error 452: out of range pointer, please open an issue in the Rufus issue tracker and make sure to indicate what ISO you are using and where you downloaded it.
