CVE Catalog

CVE-2026-53187

HighCVSS 7.1
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.13%

3th percentile - higher than 3% of all known CVEs

Summary

In the Linux kernel RDMA/core subsystem, the cpu_id attribute from user space is passed to cpumask_test_cpu() without validation, potentially causing an out-of-bounds read of the CPU bitmap. With CONFIG_DEBUG_PER_CPU_MAPS and panic_on_warn enabled, this can lead to a system reboot.

Risk Assessment

The risk includes out-of-bounds memory read and potential denial of service via system reboot triggered by an unprivileged user, impacting service availability.

Recommendation

Apply the kernel patch that validates cpu_id against nr_cpu_ids immediately. If unavailable, restrict access to the RDMA interface for untrusted users.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: RDMA/core: Validate cpu_id against nr_cpu_ids in DMAH alloc The cpu_id attribute supplied by user space through UVERBS_ATTR_ALLOC_DMAH_CPU_ID is passed directly to cpumask_test_cpu() without first verifying that the value is within the valid CPU range. Passing such untrusted data to cpumask_test_cpu() may lead to an out-of-bounds read of the underlying cpumask bitmap: the helper expands to a test_bit() that indexes the bitmap by cpu_id / BITS_PER_LONG with no bound check. In addition, on kernels built with CONFIG_DEBUG_PER_CPU_MAPS it trips the WARN_ON_ONCE() in cpumask_check(); combined with panic_on_warn this turns a bad user input into a machine reboot. Reject any cpu_id that is not smaller than nr_cpu_ids with -EINVAL before it is used. Reported by Smatch.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS