How severe is CVE-2021-42781?

CVE-2021-42781 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-2021-42781 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-42781?

CVE-2021-42781 primarily affects Redhat Enterprise Linux. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-42781?

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

When was CVE-2021-42781 published?

CVE-2021-42781 was published on 2022-04-18 and last updated on 2026-06-17.

CVE-2021-42781

CVE-2021-42781 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-787.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 3% (85th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Redhat Enterprise Linux
Published: 2022-04-18
Last modified: 2026-06-17

Description

Heap buffer overflow issues were found in Opensc before version 0.22.0 in pkcs15-oberthur.c that could potentially crash programs using the library.

Frequently asked questions

What is CVE-2021-42781?: Heap buffer overflow issues were found in Opensc before version 0.22.0 in pkcs15-oberthur.c that could potentially crash programs using the library.
How severe is CVE-2021-42781?: CVE-2021-42781 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-2021-42781 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-42781?: CVE-2021-42781 primarily affects Redhat Enterprise Linux. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-42781?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-42781 published?: CVE-2021-42781 was published on 2022-04-18 and last updated on 2026-06-17.

References

Affected products (3)

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

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