# CVE-2021-47334: linux: In the Linux kernel, the following vulnerability has been resolved:  misc/libmasm/module: Fix two use after free in i...

CVE-2021-47334 is fixed in linux on 1 platform, first by DEBIAN-CVE-2021-47334, released May 21, 2024. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2021-47334
- Priority: High
- CVSS: 7.8 (high)
- EPSS: 0.0028
- 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:  misc/libmasm/module: Fix two use after free in ibmasm_init_one  In ibmasm_init_one, it calls ibmasm_init_remote_input_dev(). Inside ibmasm_init_remote_input_dev, mouse_dev and keybd_dev are allocated by input_allocate_device(), and assigned to sp->remote.mouse_dev and sp->remote.keybd_dev respectively.  In the err_free_devices error branch of ibmasm_init_one, mouse_dev and keybd_dev are freed by input_free_device(), and return error. Then the execution runs into error_send_message error branch of ibmasm_init_one, where ibmasm_free_remote_input_dev(sp) is called to unregister the freed sp->remote.mouse_dev and sp->remote.keybd_dev.  My patch add a "error_init_remote" label to handle the error of ibmasm_init_remote_input_dev(), to avoid the uaf bugs.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 12.15 (bookworm) | 5.14.6-1 | [DEBIAN-CVE-2021-47334](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47334.md) | May 21, 2024 |
| Linux | linux Debian 13.5 (trixie) | 5.14.6-1 | [DEBIAN-CVE-2021-47334](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47334.md) | May 21, 2024 |
| Linux | linux Debian 14 | 5.14.6-1 | [DEBIAN-CVE-2021-47334](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47334.md) | May 21, 2024 |

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