# CVE-2026-64329: usb: typec: ucsi: ccg: Fix use-after-free of ucsi on remove

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2026-07-25 · Updated: 2026-08-17

## Affected

- Linux: version range not reported
- Linux: 5.5

## Description

In the Linux kernel, the following vulnerability has been resolved: usb: typec: ucsi: ccg: Fix use-after-free of ucsi on remove The threaded IRQ handler ccg_irq_handler() calls ucsi_notify_common(), which on a connector-change event calls ucsi_connector_change() and schedules connector work. In ucsi_ccg_remove(), ucsi_destroy() frees uc->ucsi (kfree) before free_irq() is called, so a handler invocation already in flight may access the freed object after ucsi_destroy(). CPU 0 (remove) | CPU 1 (threaded IRQ) ucsi_destroy(uc->ucsi) | ccg_irq_handler() kfree(ucsi) // FREE | ucsi_notify_common(uc->ucsi) // USE Move free_irq() before ucsi_destroy() in the remove path. It is kept after ucsi_unregister(): ucsi_unregister() cancels connector work whose handler issues GET_CONNECTOR_STATUS through ucsi_send_command_common(), which waits for a completion that is signalled from the IRQ handler, so the IRQ must stay active until that work has been cancelled. The probe error path already orders free_irq() before ucsi_destroy(). This bug was found by static analysis.

## What to do

- Check your stack: if you ship or depend on Linux kernel, no fixed version is listed yet; follow the vendor advisory per the references below.
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## 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/f1adeb1ff8bef1467d6961059810795d02bbad5d
- https://git.kernel.org/stable/c/99381e762273a2410a3f0216000be32b013c0ea9
- https://git.kernel.org/stable/c/1a160076d3d0dcd4a98a4599ad96eec0790b099b
- https://git.kernel.org/stable/c/c32df11147822d22facee8fa30c2e8971d12f426
- https://git.kernel.org/stable/c/86c9ee928c4a370e323e432aaf8dca79c4ba7c85
- https://git.kernel.org/stable/c/f5c772b76bbd95de8be51cf849c6098f6af6fcf9
- https://git.kernel.org/stable/c/dbb500bad02146b388041877574829016591ddc8
- https://git.kernel.org/stable/c/1f0bdc2884b67de337215079bba166df0cdf4ac5

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