CVE-2026-72105
HighCVSS 7.8Exploitation Probability (EPSS)
Low risk6th percentile - higher than 6% of all known CVEs
Summary
In the Linux kernel's dm-log module, there is a bitset_size overflow on 32-bit machines. Rounding region_count to a multiple of BITS_PER_LONG can cause wrap to zero, leading to incorrect memory allocation.
Risk Assessment
The vulnerability may lead to system crash or incorrect logging behavior, potentially affecting data integrity.
Recommendation
Apply the kernel patch that handles the bitset_size rollover case, and update your system.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: dm-log: fix a bitset_size overflow on 32bit machines Commit c20e36b7631d ("dm log: fix out-of-bounds write due to region_count overflow") made sure that region_count could fit in an unsigned int. But the bitmap memory isn't allocated based on region_count. It uses bitset_size (a size_t variable). The first step of calculating bitset_size is to set it to region_count, rounded up to a multiple of BITS_PER_LONG. If region_size is less than BITS_PER_LONG smaller than UINT_MAX, it will get rounded up to 2^32. On a 32bit architecture, this will make bitset_size wrap around to 0 and fail, despite region_count being valid. Since bitset_size gets divided by 8, it can hold any valid region_count. It just needs a special case to handle the rollover. If it is 0, the value rolled over, and bitset size should be set to the number of bytes needed to hold 2^32 bits.