# CVE-2021-42376: busybox: A NULL pointer dereference in Busybox's hush applet leads to denial of service when processing a crafted shell comman...

CVE-2021-42376 is fixed in busybox on 1 platform, first by DEBIAN-CVE-2021-42376, released November 15, 2021. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-42376
- Priority: Routine
- CVSS: 5.5 (medium)
- EPSS: 0.0043
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Nov 15, 2021

## Description

A NULL pointer dereference in Busybox's hush applet leads to denial of service when processing a crafted shell command, due to missing validation after a \x03 delimiter character. This may be used for DoS under very rare conditions of filtered command input.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | busybox Debian 12.15 (bookworm) | 1:1.35.0-1 | [DEBIAN-CVE-2021-42376](https://patchblox.com/security/data/fix/linux/debian-cve-2021-42376.md) | Nov 15, 2021 |
| Linux | busybox Debian 13.5 (trixie) | 1:1.35.0-1 | [DEBIAN-CVE-2021-42376](https://patchblox.com/security/data/fix/linux/debian-cve-2021-42376.md) | Nov 15, 2021 |
| Linux | busybox Debian 14 | 1:1.35.0-1 | [DEBIAN-CVE-2021-42376](https://patchblox.com/security/data/fix/linux/debian-cve-2021-42376.md) | Nov 15, 2021 |

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