How severe is CVE-2021-42373?

CVE-2021-42373 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-42373 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (30th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-42373?

CVE-2021-42373 primarily affects Busybox. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-42373?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-42373 published?

CVE-2021-42373 was published on 2021-11-15 and last updated on 2026-06-17.

CVE-2021-42373

CVE-2021-42373 is a medium-severity vulnerability in Busybox with a CVSS 3.x base score of 5.5. 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-476.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 2.1
EPSS exploit prediction: 0% (30th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-476
Affected product: Busybox
Published: 2021-11-15
Last modified: 2026-06-17

Description

A NULL pointer dereference in Busybox's man applet leads to denial of service when a section name is supplied but no page argument is given

Frequently asked questions

What is CVE-2021-42373?: A NULL pointer dereference in Busybox's man applet leads to denial of service when a section name is supplied but no page argument is given
How severe is CVE-2021-42373?: CVE-2021-42373 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-42373 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (30th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-42373?: CVE-2021-42373 primarily affects Busybox. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-42373?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-42373 published?: CVE-2021-42373 was published on 2021-11-15 and last updated on 2026-06-17.

References

Affected products (14)

cpe:2.3:a:busybox:busybox:1.33.0:*:*:*:*:*:*:*
cpe:2.3:a:busybox:busybox:1.33.1:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:hci_management_node:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:solidfire:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h300s_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h500s_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h700s_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h300e_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h500e_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h700e_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h410s_firmware:-:*:*:*:*:*:*:*

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