# CVE-2021-47477: linux: In the Linux kernel, the following vulnerability has been resolved:  comedi: dt9812: fix DMA buffers on stack  USB tr...

CVE-2021-47477 is fixed in linux on 1 platform, first by DEBIAN-CVE-2021-47477, released May 22, 2024. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2021-47477
- Priority: High
- CVSS: 7.8 (high)
- EPSS: 0.0072
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: May 22, 2024

## Description

In the Linux kernel, the following vulnerability has been resolved:  comedi: dt9812: fix DMA buffers on stack  USB transfer buffers are typically mapped for DMA and must not be allocated on the stack or transfers will fail.  Allocate proper transfer buffers in the various command helpers and return an error on short transfers instead of acting on random stack data.  Note that this also fixes a stack info leak on systems where DMA is not used as 32 bytes are always sent to the device regardless of how short the command is.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 12.15 (bookworm) | 5.15.3-1 | [DEBIAN-CVE-2021-47477](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47477.md) | May 22, 2024 |
| Linux | linux Debian 13.5 (trixie) | 5.15.3-1 | [DEBIAN-CVE-2021-47477](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47477.md) | May 22, 2024 |
| Linux | linux Debian 14 | 5.15.3-1 | [DEBIAN-CVE-2021-47477](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47477.md) | May 22, 2024 |

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Data as of 2026-11-08T06:59:42Z 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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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