# CVE-2021-39656: linux: In __configfs_open_file of file.c, there is a possible use-after-free due to improper locking

CVE-2021-39656 is fixed in linux on 1 platform, first by DEBIAN-CVE-2021-39656, released December 15, 2021. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-39656
- Priority: Routine
- CVSS: 6.7 (medium)
- EPSS: 0.0012
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Dec 15, 2021

## Description

In __configfs_open_file of file.c, there is a possible use-after-free due to improper locking. This could lead to local escalation of privilege in the kernel with System execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android kernelAndroid ID: A-174049066References: Upstream kernel

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 12.15 (bookworm) | 5.10.24-1 | [DEBIAN-CVE-2021-39656](https://patchblox.com/security/data/fix/linux/debian-cve-2021-39656.md) | Dec 15, 2021 |
| Linux | linux Debian 13.5 (trixie) | 5.10.24-1 | [DEBIAN-CVE-2021-39656](https://patchblox.com/security/data/fix/linux/debian-cve-2021-39656.md) | Dec 15, 2021 |
| Linux | linux Debian 14 | 5.10.24-1 | [DEBIAN-CVE-2021-39656](https://patchblox.com/security/data/fix/linux/debian-cve-2021-39656.md) | Dec 15, 2021 |

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