How severe is CVE-2021-42779?

CVE-2021-42779 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2021-42779 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-42779?

CVE-2021-42779 primarily affects Redhat Enterprise Linux. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-42779?

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

When was CVE-2021-42779 published?

CVE-2021-42779 was published on 2022-04-18 and last updated on 2026-06-17.

CVE-2021-42779

CVE-2021-42779 is a medium-severity vulnerability in Redhat Enterprise Linux with a CVSS 3.x base score of 5.3. 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: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 2% (79th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-416
Affected product: Redhat Enterprise Linux
Published: 2022-04-18
Last modified: 2026-06-17

Description

A heap use after free issue was found in Opensc before version 0.22.0 in sc_file_valid.

Frequently asked questions

What is CVE-2021-42779?: A heap use after free issue was found in Opensc before version 0.22.0 in sc_file_valid.
How severe is CVE-2021-42779?: CVE-2021-42779 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2021-42779 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-42779?: CVE-2021-42779 primarily affects Redhat Enterprise Linux. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-42779?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-42779 published?: CVE-2021-42779 was published on 2022-04-18 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:opensc_project:opensc:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*

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