How severe is CVE-2021-35942?

CVE-2021-35942 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability high.

Is CVE-2021-35942 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-35942?

CVE-2021-35942 primarily affects Gnu Glibc. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-35942?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2021-35942 published?

CVE-2021-35942 was published on 2021-07-22 and last updated on 2026-06-17.

CVE-2021-35942

CVE-2021-35942 is a critical-severity vulnerability in Gnu Glibc with a CVSS 3.x base score of 9.1. 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-190.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
CVSS v2: 6.4
EPSS exploit prediction: 3% (84th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-190
Affected product: Gnu Glibc
Published: 2021-07-22
Last modified: 2026-06-17

Description

The wordexp function in the GNU C Library (aka glibc) through 2.33 may crash or read arbitrary memory in parse_param (in posix/wordexp.c) when called with an untrusted, crafted pattern, potentially resulting in a denial of service or disclosure of information. This occurs because atoi was used but strtoul should have been used to ensure correct calculations.

Frequently asked questions

What is CVE-2021-35942?: The wordexp function in the GNU C Library (aka glibc) through 2.33 may crash or read arbitrary memory in parse_param (in posix/wordexp.c) when called with an untrusted, crafted pattern, potentially resulting in a denial of service or disclosure of information. This occurs because atoi was used but strtoul should have been used to ensure correct calculations.
How severe is CVE-2021-35942?: CVE-2021-35942 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability high.
Is CVE-2021-35942 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-35942?: CVE-2021-35942 primarily affects Gnu Glibc. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-35942?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-35942 published?: CVE-2021-35942 was published on 2021-07-22 and last updated on 2026-06-17.

References

Affected products (7)

cpe:2.3:a:gnu:glibc:*:*:*:*:*:*:*:*
cpe:2.3:a:netapp:active_iq_unified_manager:-:*:*:*:*:vmware_vsphere:*:*
cpe:2.3:a:netapp:e-series_santricity_os_controller:*:*:*:*:*:*:*:*
cpe:2.3:a:netapp:hci_management_node:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:ontap_select_deploy_administration_utility:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:solidfire:-:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*

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