How severe is CVE-2021-46880?

CVE-2021-46880 has a CVSS 3.x base score of 9.8, 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 high, and availability high.

Is CVE-2021-46880 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-46880?

CVE-2021-46880 primarily affects Openbsd Libressl. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-46880?

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-2021-46880 published?

CVE-2021-46880 was published on 2023-04-15 and last updated on 2026-06-17.

CVE-2021-46880

CVE-2021-46880 is a critical-severity vulnerability in Openbsd Libressl with a CVSS 3.x base score of 9.8. 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-295.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 1% (43rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Openbsd Libressl
Published: 2023-04-15
Last modified: 2026-06-17

Description

x509/x509_verify.c in LibreSSL before 3.4.2, and OpenBSD before 7.0 errata 006, allows authentication bypass because an error for an unverified certificate chain is sometimes discarded.

Frequently asked questions

What is CVE-2021-46880?: x509/x509_verify.c in LibreSSL before 3.4.2, and OpenBSD before 7.0 errata 006, allows authentication bypass because an error for an unverified certificate chain is sometimes discarded.
How severe is CVE-2021-46880?: CVE-2021-46880 has a CVSS 3.x base score of 9.8, 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 high, and availability high.
Is CVE-2021-46880 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-46880?: CVE-2021-46880 primarily affects Openbsd Libressl. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-46880?: 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-2021-46880 published?: CVE-2021-46880 was published on 2023-04-15 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:openbsd:libressl:*:*:*:*:*:*:*:*
cpe:2.3:o:openbsd:openbsd:*:*:*:*:*:*:*:*

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