Description
A flaw was found in grub2. When performing a symlink lookup from a reiserfs filesystem, grub's reiserfs fs module uses user-controlled parameters from the filesystem geometry to determine the internal buffer size, however, it improperly checks for integer overflows. A maliciouly crafted filesystem may lead some of those buffer size calculations to overflow, causing it to perform a grub_malloc() operation with a smaller size than expected. As a result, the grub_reiserfs_read_symlink() will call grub_reiserfs_read_real() with a overflown length parameter, leading to a heap based out-of-bounds write during data reading. This flaw may be leveraged to corrupt grub's internal critical data and can result in arbitrary code execution, by-passing secure boot protections.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
grub2
Default version status: unaffected
0 to ≤ 2.12affected
Red Hat Red Hat Enterprise Linux 10
Default version status: unaffected
Red Hat Red Hat Enterprise Linux 7
Default version status: unaffected
Red Hat Red Hat Enterprise Linux 8
Default version status: unaffected
Red Hat Red Hat Enterprise Linux 9
Default version status: unaffected
Red Hat Red Hat OpenShift Container Platform 4
Default version status: unaffected
Red Hat Red Hat OpenShift Container Platform 4
Default version status: unaffected