GRUB2 does not call the module fini functions on exit, leading to Debian/Ubuntus peimage GRUB2 module leaving UEFI system table hooks after exit. This lead to a use-after-free condition, and could possibly lead to secure boot bypass.
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Grub2 | Gnu | * | 2.12-1ubuntu5 (excluding) |
| Grub2 | Ubuntu | bionic | * |
| Grub2 | Ubuntu | esm-infra-legacy/trusty | * |
| Grub2 | Ubuntu | trusty | * |
| Grub2 | Ubuntu | trusty/esm | * |
| Grub2 | Ubuntu | xenial | * |
| Grub2-signed | Ubuntu | bionic | * |
| Grub2-signed | Ubuntu | devel | * |
| Grub2-signed | Ubuntu | esm-infra-legacy/trusty | * |
| Grub2-signed | Ubuntu | mantic | * |
| Grub2-signed | Ubuntu | noble | * |
| Grub2-signed | Ubuntu | oracular | * |
| Grub2-signed | Ubuntu | trusty | * |
| Grub2-signed | Ubuntu | trusty/esm | * |
| Grub2-signed | Ubuntu | xenial | * |
| Grub2-unsigned | Ubuntu | bionic | * |
| Grub2-unsigned | Ubuntu | devel | * |
| Grub2-unsigned | Ubuntu | mantic | * |
| Grub2-unsigned | Ubuntu | noble | * |
| Grub2-unsigned | Ubuntu | oracular | * |
| Grub2-unsigned | Ubuntu | trusty | * |
| Grub2-unsigned | Ubuntu | xenial | * |