CVE Catalog

CVE-2021-47368

HighCVSS 7.1
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.64%

47th percentile - higher than 47% of all known CVEs

Summary

In the Linux kernel's enetc driver, there is an illegal memory access when reading the affinity_hint file in procfs. irq_set_affinity_hit() stores a reference to a temporary stack variable, leading to a page fault on later access. The issue is fixed by the get_cpu_mask() helper, which provides permanent storage.

Risk Assessment

An attacker with local access can cause a system crash (oops) by reading the affinity_hint file, leading to denial of service.

Recommendation

Apply a Linux kernel update containing the fix for this issue. If not possible, restrict access to procfs for unprivileged users.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: enetc: Fix illegal access when reading affinity_hint irq_set_affinity_hit() stores a reference to the cpumask_t parameter in the irq descriptor, and that reference can be accessed later from irq_affinity_hint_proc_show(). Since the cpu_mask parameter passed to irq_set_affinity_hit() has only temporary storage (it's on the stack memory), later accesses to it are illegal. Thus reads from the corresponding procfs affinity_hint file can result in paging request oops. The issue is fixed by the get_cpu_mask() helper, which provides a permanent storage for the cpumask_t parameter.

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