Security readout for executives and security teams
Plain-English summary
BusyBox includes a vulnerable awk component. If a crafted awk pattern is processed, the flaw can crash the process and may allow code execution. The sources do not show active exploitation, but BusyBox is widely reused in Linux distributions, embedded systems, and appliances, making inventory important.
Executive priority
Treat as a high-priority hygiene and exposure-management issue for Linux, embedded, and appliance estates. Escalate where BusyBox awk processes untrusted input or runs inside privileged automation. Prioritize vendor updates over custom mitigations because fixed versions are not provided in the bundle.
Technical view
CVE-2021-42382 is a CWE-416 use-after-free in BusyBox awk, specifically getvar_s, triggered while processing a crafted awk pattern. CVSS 3.1 is 7.2 high with network attack vector, low complexity, high privileges required, no user interaction, and high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is most likely where BusyBox awk is present in Linux packages, firmware, containers, or appliances. The bundle cites Fedora, Debian LTS, and NetApp advisories, indicating downstream vendors evaluated impact. Exact affected versions are not specified in the provided CVE data.
Exploitation context
The bundle says denial of service and possible code execution, but does not cite public exploitation. KEV is false. Practical risk depends on whether privileged users or services can make BusyBox awk process attacker-controlled awk patterns.
Researcher notes
Evidence supports a use-after-free in BusyBox awk getvar_s with DoS and possible code execution impact. The CVSS privileges requirement is high, so validation should focus on privileged execution paths and downstream packaging. The source bundle does not provide exploit details or exact affected version boundaries.
Mitigation direction
- Inventory BusyBox installations, including firmware, appliances, containers, and statically bundled binaries.
- Apply fixed BusyBox packages or firmware updates from the relevant OS or product vendor.
- Check Fedora, Debian LTS, NetApp, and other vendor advisories for product-specific guidance.
- Reduce or remove workflows that pass untrusted awk patterns to BusyBox awk.
- Monitor vendor advisories if exact fixed versions are missing from local asset data.
Validation and detection
- Identify BusyBox versions and confirm whether the awk applet is enabled or used.
- Map each asset to vendor advisories and available patched package or firmware releases.
- Review scripts and services for attacker-controlled input reaching BusyBox awk patterns.
- Check logs for crashes or abnormal failures in awk-invoking services.
- Record that no cited source confirms active exploitation in this bundle.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-416: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-42382 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.2 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H1.25.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.2HighVector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://jfrog.com/blog/unboxing-busybox-14-new-vulnerabilities-uncovered-by-claroty-and-jfrog/CVE reference
- FEDORA-2021-5a95823596CVE reference · vendor-advisory
- FEDORA-2021-c52c0fe490CVE reference · vendor-advisory
- https://security.netapp.com/advisory/ntap-20211223-0002/CVE reference
- https://claroty.com/team82/research/unboxing-busybox-14-vulnerabilities-uncovered-by-claroty-jfrogCVE reference
- https://lists.debian.org/debian-lts-announce/2025/01/msg00012.htmlCVE reference
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Use After Free
Use After Free represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.