CVE catalog

CVE-2021-42379

busybox: CVE-2021-42379

Severity: Medium · CVSS 6.6CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
Published: Nov 9, 2021, 11:00:00 PM UTC
Source: [NVD] · [CVE record]
EPSS: 2.79% · Oct 25, 2026

A use-after-free in Busybox's awk applet leads to denial of service and possibly code execution when processing a crafted awk pattern in the next_input_file function

Vulnerable and fixed packages

Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.

Distribution	Package	Release	Version	Status
Debian	busybox	sid	`1:1.38.0-3`	fixed
Debian	busybox	forky	`1:1.38.0-3`	fixed
Debian	busybox	trixie	`1:1.37.0-6`	fixed
Debian	busybox	bookworm	`1:1.35.0-4+deb12u1`	fixed
Alpine	busybox	3.11	`1.31.1-r11`	fixed
Alpine	busybox	3.12	`1.31.1-r21`	fixed
Alpine	busybox	3.13	`1.32.1-r7`	fixed
Alpine	busybox	3.14	`1.33.1-r6`	fixed
Alpine	busybox	3.15	`1.34.0-r0`	fixed
Alpine	busybox	3.16	`1.34.0-r0`	fixed
Alpine	busybox	3.17	`1.34.0-r0`	fixed
Alpine	busybox	3.18	`1.34.0-r0`	fixed
Alpine	busybox	3.19	`1.34.0-r0`	fixed
Alpine	busybox	3.20	`1.34.0-r0`	fixed
Alpine	busybox	3.21	`1.34.0-r0`	fixed
Alpine	busybox	3.22	`1.34.0-r0`	fixed
Alpine	busybox	3.23	`1.34.0-r0`	fixed
Alpine	busybox	3.24	`1.34.0-r0`	fixed
Ubuntu	busybox	pro	`1:1.22.0-15ubuntu1`	vulnerable
Ubuntu	busybox	pro	`1:1.22.0-15ubuntu1.4`	vulnerable
Ubuntu	busybox	pro	`1:1.22.0-15ubuntu1.4+esm1`	vulnerable
Ubuntu	busybox	pro	`1:1.22.0-15ubuntu1.4+esm2`	vulnerable
Ubuntu	busybox	18.04	`1:1.22.0-19ubuntu2`	vulnerable
Ubuntu	busybox	18.04	`1:1.27.2-1ubuntu3`	vulnerable
Ubuntu	busybox	18.04	`1:1.27.2-1ubuntu4`	vulnerable
Ubuntu	busybox	18.04	`1:1.27.2-2ubuntu2`	vulnerable
Ubuntu	busybox	18.04	`1:1.27.2-2ubuntu3`	vulnerable
Ubuntu	busybox	18.04	`1:1.27.2-2ubuntu3.1`	vulnerable
Ubuntu	busybox	18.04	`1:1.27.2-2ubuntu3.2`	vulnerable
Ubuntu	busybox	18.04	`1:1.27.2-2ubuntu3.3`	vulnerable
Ubuntu	busybox	18.04	`1:1.27.2-2ubuntu3.4`	fixed
Ubuntu	busybox	20.04	`1:1.30.1-4ubuntu4`	vulnerable
Ubuntu	busybox	20.04	`1:1.30.1-4ubuntu5`	vulnerable
Ubuntu	busybox	20.04	`1:1.30.1-4ubuntu6`	vulnerable
Ubuntu	busybox	20.04	`1:1.30.1-4ubuntu6.1`	vulnerable
Ubuntu	busybox	20.04	`1:1.30.1-4ubuntu6.2`	vulnerable
Ubuntu	busybox	20.04	`1:1.30.1-4ubuntu6.3`	vulnerable
Ubuntu	busybox	20.04	`1:1.30.1-4ubuntu6.4`	fixed
Ubuntu	busybox	22.04	`1:1.30.1-6ubuntu3`	vulnerable
Ubuntu	busybox	22.04	`1:1.30.1-7ubuntu1`	vulnerable
Ubuntu	busybox	22.04	`1:1.30.1-7ubuntu2`	fixed

Fixed-version evidence

Distribution	Package	Type	Release	Fixed version	Urgency	Origin	Bugs
Debian	busybox	source	sid	`1:1.35.0-1`	not yet assigned	Not reported	[999567]
Debian	busybox	source	forky	`1:1.35.0-1`	not yet assigned	Not reported	[999567]
Debian	busybox	source	trixie	`1:1.35.0-1`	not yet assigned	Not reported	[999567]
Debian	busybox	source	bookworm	`1:1.35.0-1`	not yet assigned	Not reported	[999567]
Alpine	busybox	apk	3.11	`1.31.1-r11`	Not reported	ALPINE-CVE-2021-42379	Not reported
Alpine	busybox	apk	3.12	`1.31.1-r21`	Not reported	ALPINE-CVE-2021-42379	Not reported
Alpine	busybox	apk	3.13	`1.32.1-r7`	Not reported	ALPINE-CVE-2021-42379	Not reported
Alpine	busybox	apk	3.14	`1.33.1-r6`	Not reported	ALPINE-CVE-2021-42379	Not reported
Alpine	busybox	apk	3.15	`1.34.0-r0`	Not reported	ALPINE-CVE-2021-42379	Not reported
Alpine	busybox	apk	3.16	`1.34.0-r0`	Not reported	ALPINE-CVE-2021-42379	Not reported
Alpine	busybox	apk	3.17	`1.34.0-r0`	Not reported	ALPINE-CVE-2021-42379	Not reported
Alpine	busybox	apk	3.18	`1.34.0-r0`	Not reported	ALPINE-CVE-2021-42379	Not reported
Alpine	busybox	apk	3.19	`1.34.0-r0`	Not reported	ALPINE-CVE-2021-42379	Not reported
Alpine	busybox	apk	3.20	`1.34.0-r0`	Not reported	ALPINE-CVE-2021-42379	Not reported
Alpine	busybox	apk	3.21	`1.34.0-r0`	Not reported	ALPINE-CVE-2021-42379	Not reported
Alpine	busybox	apk	3.22	`1.34.0-r0`	Not reported	ALPINE-CVE-2021-42379	Not reported
Alpine	busybox	apk	3.23	`1.34.0-r0`	Not reported	ALPINE-CVE-2021-42379	Not reported
Alpine	busybox	apk	3.24	`1.34.0-r0`	Not reported	ALPINE-CVE-2021-42379	Not reported
Ubuntu	busybox	deb	18.04	`1:1.27.2-2ubuntu3.4`	Not reported	UBUNTU-CVE-2021-42379	Not reported
Ubuntu	busybox	deb	20.04	`1:1.30.1-4ubuntu6.4`	Not reported	UBUNTU-CVE-2021-42379	Not reported
Ubuntu	busybox	deb	22.04	`1:1.30.1-7ubuntu2`	Not reported	UBUNTU-CVE-2021-42379	Not reported

[Debian bug #999567]

OpenFactory catalog packages

[Debian 12 (Bookworm)]

[busybox]Fixed
Source package: [busybox]
Details (2)
- 1:1.35.0-4+deb12u1+b1 · amd64 · bookworm
  Fixed · Fixed: 1:1.35.0-1
  dsa · busybox · debian · bookworm; dsa · busybox · debian · 12
- 1:1.35.0-4+deb12u1+b1 · arm64 · bookworm
  Fixed · Fixed: 1:1.35.0-1
  dsa · busybox · debian · bookworm; dsa · busybox · debian · 12
[busybox-static]Fixed
Source package: [busybox]
Details (2)
- 1:1.35.0-4+deb12u1+b1 · amd64 · bookworm
  Fixed · Fixed: 1:1.35.0-1
  dsa · busybox · debian · bookworm; dsa · busybox · debian · 12
- 1:1.35.0-4+deb12u1+b1 · arm64 · bookworm
  Fixed · Fixed: 1:1.35.0-1
  dsa · busybox · debian · bookworm; dsa · busybox · debian · 12
[busybox-syslogd]Fixed
Source package: [busybox]
Details (2)
- 1:1.35.0-4+deb12u1 · all · bookworm
  Fixed · Fixed: 1:1.35.0-1
  dsa · busybox · debian · bookworm; dsa · busybox · debian · 12
- 1:1.35.0-4+deb12u1 · all · bookworm
  Fixed · Fixed: 1:1.35.0-1
  dsa · busybox · debian · bookworm; dsa · busybox · debian · 12
[udhcpc]Fixed
Source package: [busybox]
Details (2)
- 1:1.35.0-4+deb12u1+b1 · amd64 · bookworm
  Fixed · Fixed: 1:1.35.0-1
  dsa · busybox · debian · bookworm; dsa · busybox · debian · 12
- 1:1.35.0-4+deb12u1+b1 · arm64 · bookworm
  Fixed · Fixed: 1:1.35.0-1
  dsa · busybox · debian · bookworm; dsa · busybox · debian · 12
[udhcpd]Fixed
Source package: [busybox]
Details (2)
- 1:1.35.0-4+deb12u1+b1 · amd64 · bookworm
  Fixed · Fixed: 1:1.35.0-1
  dsa · busybox · debian · bookworm; dsa · busybox · debian · 12
- 1:1.35.0-4+deb12u1+b1 · arm64 · bookworm
  Fixed · Fixed: 1:1.35.0-1
  dsa · busybox · debian · bookworm; dsa · busybox · debian · 12

[Debian 13 (Trixie)]

[busybox]Fixed
Source package: [busybox]
Details (2)
- 1:1.37.0-6+b8 · amd64 · trixie
  Fixed · Fixed: 1:1.35.0-1
  dsa · busybox · debian · 13
- 1:1.37.0-6+b8 · arm64 · trixie
  Fixed · Fixed: 1:1.35.0-1
  dsa · busybox · debian · 13
[busybox-static]Fixed
Source package: [busybox]
Details (2)
- 1:1.37.0-6+b8 · amd64 · trixie
  Fixed · Fixed: 1:1.35.0-1
  dsa · busybox · debian · 13
- 1:1.37.0-6+b8 · arm64 · trixie
  Fixed · Fixed: 1:1.35.0-1
  dsa · busybox · debian · 13
[busybox-syslogd]Fixed
Source package: [busybox]
Details (2)
- 1:1.37.0-6 · all · trixie
  Fixed · Fixed: 1:1.35.0-1
  dsa · busybox · debian · 13
- 1:1.37.0-6 · all · trixie
  Fixed · Fixed: 1:1.35.0-1
  dsa · busybox · debian · 13
[udhcpc]Fixed
Source package: [busybox]
Details (2)
- 1:1.37.0-6 · all · trixie
  Fixed · Fixed: 1:1.35.0-1
  dsa · busybox · debian · 13
- 1:1.37.0-6 · all · trixie
  Fixed · Fixed: 1:1.35.0-1
  dsa · busybox · debian · 13
[udhcpd]Fixed
Source package: [busybox]
Details (2)
- 1:1.37.0-6 · all · trixie
  Fixed · Fixed: 1:1.35.0-1
  dsa · busybox · debian · 13
- 1:1.37.0-6 · all · trixie
  Fixed · Fixed: 1:1.35.0-1
  dsa · busybox · debian · 13

Observed: Oct 23, 2026, 6:03:12 PM UTC

References

[CERT-Bund public advisories] · [CISA cybersecurity advisories] · [Debian Security Tracker] · [FIRST EPSS] · [OSV Package Vulnerability Database] · [SUSE security advisories and VEX]