CVE-2021-42376: busybox NULL Pointer Dereference
CVSS: 5.5v3.1MediumModified
AliasesALPINE-CVE-2021-42376DEBIAN-CVE-2021-42376
Published 15-11-2021Last modified 04-08-2024
Vulnerability summary
CVE-2021-42376 is a medium (CVSS 5.5) NULL Pointer Dereference vulnerability in busybox. EPSS estimates a 0.43% chance of exploitation in the next 30 days, higher than 36.2% of scored vulnerabilities.
CVSS score
5.5/10
010
Medium · v3.1 (NVD)EPSS score
0.43%
0%100%
Low · 0.00 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 6 · Related 5Timeline
- 15-11-2021PublishedVulnerability first disclosed.
- 04-08-2024Last modifiedVulnerability information updated.
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.
CVSS metrics
4 scores · 3 sources · 2 versionsMedium 5.5Preferred score · NVD (NIST)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HSourcesAll 3 agree
- OSV · AlpineEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Low 1.9Preferred score · NVD (NIST)
AV:L/AC:M/Au:N/C:N/I:N/A:PSourcesSingle source
EPSS trend
Probability
0.43%
Chance of exploitation in the next 30 days
Percentile
36%
Versus all other CVEs
30-day change
0.00 pp
From 0.43% on 20-09-2026
20-09-202620-10-2026
EPSS score0.43%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Alpine1 product
- busybox≥ 1.16.0 (No fix recorded)
Busybox1 product
- busybox≥ unspecified, < 1.34.0 | ≥ 1.16.0, < 1.34.0
Debian1 product
- busybox< 1:1.35.0-1
Fedoraproject1 product
- fedoraEOL33 | 34
5 vendors · 14 products
References
8 links- lists.fedoraproject.org/archives/…Vendor Advisory
- lists.fedoraproject.org/archives/…Vendor Advisory
- security.netapp.com/advisory/ntap-20211223-0002/Third Party Advisory