CVE Catalog

CVE-2026-90178

Low risk· EPSS 6%
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.17%

6th percentile - higher than 6% of all known CVEs

Summary

In the Linux kernel, the hwmon coretemp driver has a memory leak of the pdata->core_data array on CPUs that do not support X86_FEATURE_PTS. The array is allocated in init_temp_data() but only freed in destroy_temp_data(), which is never called for package data when pkg_data remains NULL. The fix releases the array in coretemp_device_remove().

Risk Assessment

The kernel memory leak gradually exhausts system resources on each load and unload cycle of the coretemp module, potentially leading to instability or system failure on affected CPUs.

Recommendation

Update the Linux kernel to a version containing the fix for CVE-2026-90178 or apply the relevant patch provided by your distribution. Until then, avoid repeatedly loading and unloading the coretemp module.

Related vulnerabilities

Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: hwmon: (coretemp) Fix core_data leak on CPUs without PTS pdata->core_data is allocated in init_temp_data() when the first core temp_data of a package is created, but it is only released from destroy_temp_data(), and only in the branch that handles the package temp_data. Package temp_data is created solely when the CPU supports X86_FEATURE_PTS. On a CPU without it, coretemp_cpu_online() never calls coretemp_add_core() with pkg_flag set, so pdata->pkg_data stays NULL. coretemp_cpu_offline() then skips the removal of the package interface, destroy_temp_data() is never called for package data, and the array is still allocated when coretemp_device_remove() frees the platform data that pointed at it. Release the array in coretemp_device_remove(). destroy_temp_data() sets pdata->core_data to NULL when it frees it, so the added kfree() is a no-op on CPUs that do have PTS. Tested on an Intel Core i5-1135G7. The driver was instrumented to log every allocation and release of pdata->core_data, and the PTS check in coretemp_cpu_online() was patched out to emulate a CPU without package thermal support. Without this change the array was allocated and never released, and coretemp_device_remove() still saw a non-NULL pointer. With it the array is released and the pointer accounting balances. On an unmodified build the release still happens via the package temp_data and the added kfree() sees NULL, with no slab warnings over repeated module load and unload cycles.

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