# CVE-2021-47500: linux: In the Linux kernel, the following vulnerability has been resolved:  iio: mma8452: Fix trigger reference couting  The...

CVE-2021-47500 is fixed in linux on 1 platform, first by DEBIAN-CVE-2021-47500, released May 24, 2024. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2021-47500
- Priority: High
- CVSS: 7.8 (high)
- EPSS: 0.0024
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: May 24, 2024

## Description

In the Linux kernel, the following vulnerability has been resolved:  iio: mma8452: Fix trigger reference couting  The mma8452 driver directly assigns a trigger to the struct iio_dev. The IIO core when done using this trigger will call `iio_trigger_put()` to drop the reference count by 1.  Without the matching `iio_trigger_get()` in the driver the reference count can reach 0 too early, the trigger gets freed while still in use and a use-after-free occurs.  Fix this by getting a reference to the trigger before assigning it to the IIO device.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 12.15 (bookworm) | 5.15.15-1 | [DEBIAN-CVE-2021-47500](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47500.md) | May 24, 2024 |
| Linux | linux Debian 13.5 (trixie) | 5.15.15-1 | [DEBIAN-CVE-2021-47500](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47500.md) | May 24, 2024 |
| Linux | linux Debian 14 | 5.15.15-1 | [DEBIAN-CVE-2021-47500](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47500.md) | May 24, 2024 |

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