CVE-2021-42379
CVE-2021-42379 is a high-severity vulnerability in Busybox with a CVSS 3.x base score of 7.2. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-416.
Key facts
- Severity: High (CVSS 3.x base score 7.2)
- CVSS v2: 6.5
- EPSS exploit prediction: 3% (83rd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-416
- Affected product: Busybox
- Published:
- Last modified:
Description
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
Frequently asked questions
- What is CVE-2021-42379?
- 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
- How severe is CVE-2021-42379?
- CVE-2021-42379 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-42379 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-42379?
- CVE-2021-42379 primarily affects Busybox. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-42379?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2021-42379 published?
- CVE-2021-42379 was published on 2021-11-15 and last updated on 2026-06-17.
References
- https://claroty.com/team82/research/unboxing-busybox-14-vulnerabilities-uncovered-by-claroty-jfrog
- https://jfrog.com/blog/unboxing-busybox-14-new-vulnerabilities-uncovered-by-claroty-and-jfrog/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6T2TURBYYJGBMQTTN2DSOAIQGP7WCPGV/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UQXGOGWBIYWOIVXJVRKHZR34UMEHQBXS/
- https://security.netapp.com/advisory/ntap-20211223-0002/
- https://lists.debian.org/debian-lts-announce/2025/01/msg00012.html
Affected products (3)
- cpe:2.3:a:busybox:busybox:*:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
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