# CVE-2021-47239: linux: In the Linux kernel, the following vulnerability has been resolved:  net: usb: fix possible use-after-free in smsc75x...

CVE-2021-47239 is fixed in linux on 1 platform, first by DEBIAN-CVE-2021-47239, released May 21, 2024. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2021-47239
- Priority: High
- CVSS: 7.8 (high)
- EPSS: 0.0023
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: May 21, 2024

## Description

In the Linux kernel, the following vulnerability has been resolved:  net: usb: fix possible use-after-free in smsc75xx_bind  The commit 46a8b29c6306 ("net: usb: fix memory leak in smsc75xx_bind") fails to clean up the work scheduled in smsc75xx_reset-> smsc75xx_set_multicast, which leads to use-after-free if the work is scheduled to start after the deallocation. In addition, this patch also removes a dangling pointer - dev->data[0].  This patch calls cancel_work_sync to cancel the scheduled work and set the dangling pointer to NULL.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 12.15 (bookworm) | 5.10.46-1 | [DEBIAN-CVE-2021-47239](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47239.md) | May 21, 2024 |
| Linux | linux Debian 13.5 (trixie) | 5.10.46-1 | [DEBIAN-CVE-2021-47239](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47239.md) | May 21, 2024 |
| Linux | linux Debian 14 | 5.10.46-1 | [DEBIAN-CVE-2021-47239](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47239.md) | May 21, 2024 |

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