# CVE-2021-47511: linux: In the Linux kernel, the following vulnerability has been resolved:  ALSA: pcm: oss: Fix negative period/buffer sizes...

CVE-2021-47511 is fixed in linux on 1 platform, first by DEBIAN-CVE-2021-47511, released May 24, 2024. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-47511
- Priority: Routine
- CVSS: 5.5 (medium)
- 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:  ALSA: pcm: oss: Fix negative period/buffer sizes  The period size calculation in OSS layer may receive a negative value as an error, but the code there assumes only the positive values and handle them with size_t.  Due to that, a too big value may be passed to the lower layers.  This patch changes the code to handle with ssize_t and adds the proper error checks appropriately.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 12.15 (bookworm) | 5.15.15-1 | [DEBIAN-CVE-2021-47511](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47511.md) | May 24, 2024 |
| Linux | linux Debian 13.5 (trixie) | 5.15.15-1 | [DEBIAN-CVE-2021-47511](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47511.md) | May 24, 2024 |
| Linux | linux Debian 14 | 5.15.15-1 | [DEBIAN-CVE-2021-47511](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47511.md) | May 24, 2024 |

---

Data as of 2026-11-09T01:18:40Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.