# CVE-2021-47294: linux: In the Linux kernel, the following vulnerability has been resolved:  netrom: Decrease sock refcount when sock timers...

CVE-2021-47294 is fixed in linux on 1 platform, first by DEBIAN-CVE-2021-47294, released May 21, 2024. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-47294
- Priority: Routine
- CVSS: 5.5 (medium)
- 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:  netrom: Decrease sock refcount when sock timers expire  Commit 63346650c1a9 ("netrom: switch to sock timer API") switched to use sock timer API. It replaces mod_timer() by sk_reset_timer(), and del_timer() by sk_stop_timer().  Function sk_reset_timer() will increase the refcount of sock if it is called on an inactive timer, hence, in case the timer expires, we need to decrease the refcount ourselves in the handler, otherwise, the sock refcount will be unbalanced and the sock will never be freed.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 12.15 (bookworm) | 5.14.6-1 | [DEBIAN-CVE-2021-47294](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47294.md) | May 21, 2024 |
| Linux | linux Debian 13.5 (trixie) | 5.14.6-1 | [DEBIAN-CVE-2021-47294](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47294.md) | May 21, 2024 |
| Linux | linux Debian 14 | 5.14.6-1 | [DEBIAN-CVE-2021-47294](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47294.md) | May 21, 2024 |

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