CVE-2021-42377
Publication date 15 November 2021
Last updated 25 August 2025
Ubuntu priority
Description
An attacker-controlled pointer free in Busybox's hush applet leads to denial of service and possible code execution when processing a crafted shell command, due to the shell mishandling the &&& string. This may be used for remote code execution under rare conditions of filtered command input.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| busybox | 22.04 LTS jammy |
Not affected
|
| 20.04 LTS focal |
Not affected
|
|
| 18.04 LTS bionic |
Not affected
|
|
| 16.04 LTS xenial |
Not affected
|
|
| 14.04 LTS trusty |
Not affected
|
Notes
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score |
9.8 · Critical
|
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | None |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | High |
| Integrity impact | High |
| Availability impact | High |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |