CVE-2026-53187

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description An issue exists in the RDMA/core component where the cpu id attribute, provided by user space via UVERBS ATTR ALLOC DMAH CPU ID, is passed to the cpumask test cpu() function without verifying if the value falls within the valid CPU range. This lack of validation can lead to an out-of-bounds read of the underlying cpumask bitmap, as the helper function uses test bit() to index the bitmap by cpu id / BITS PER LONG without a bound check. Furthermore, on kernels compiled with CONFIG DEBUG PER CPU MAPS, this can trigger a WARN ON ONCE() in cpumask check(), which may cause a system reboot if panic on warn is enabled.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.