Vulnerability Database

356,688

Total vulnerabilities in the database

CVE-2026-31744 — linux / linux_kernel

NULL Pointer Dereference

In the Linux kernel, the following vulnerability has been resolved:

PM: EM: Fix NULL pointer dereference when perf domain ID is not found

dev_energymodel_nl_get_perf_domains_doit() calls em_perf_domain_get_by_id() but does not check the return value before passing it to __em_nl_get_pd_size(). When a caller supplies a non-existent perf domain ID, em_perf_domain_get_by_id() returns NULL, and __em_nl_get_pd_size() immediately dereferences pd->cpus (struct offset 0x30), causing a NULL pointer dereference.

The sister handler dev_energymodel_nl_get_perf_table_doit() already handles this correctly via __em_nl_get_pd_table_id(), which returns NULL and causes the caller to return -EINVAL. Add the same NULL check in the get-perf-domains do handler.

[ rjw: Subject and changelog edits ]

  • Published: May 1, 2026
  • Updated: May 8, 2026
  • CVE: CVE-2026-31744
  • Severity: Medium
  • Exploit:
  • CISA KEV:

CVSS v3:

  • Severity: Medium
  • Score: 5.5
  • AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CWEs:

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