How severe is CVE-2026-33810?

CVE-2026-33810 has a CVSS 3.x base score of 8.2, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability none.

Is CVE-2026-33810 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-33810?

CVE-2026-33810 affects Golang Go. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-33810?

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

Does CVE-2026-33810 have an EU (EUVD) identifier?

Yes. CVE-2026-33810 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-20024.

When was CVE-2026-33810 published?

CVE-2026-33810 was published on 2026-04-08 and last updated on 2026-07-06.

CVE-2026-33810

CVE-2026-33810 is a high-severity vulnerability in Golang Go with a CVSS 3.x base score of 8.2. 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: High (CVSS 3.x base score 8.2)
EPSS exploit prediction: 0% (26th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-20024
Weakness: CWE-295
Affected product: Golang Go
Published: 2026-04-08
Last modified: 2026-07-06

Description

When verifying a certificate chain containing excluded DNS constraints, these constraints are not correctly applied to wildcard DNS SANs which use a different case than the constraint. This only affects validation of otherwise trusted certificate chains, issued by a root CA in the VerifyOptions.Roots CertPool, or in the system certificate pool.

Frequently asked questions

What is CVE-2026-33810?: When verifying a certificate chain containing excluded DNS constraints, these constraints are not correctly applied to wildcard DNS SANs which use a different case than the constraint. This only affects validation of otherwise trusted certificate chains, issued by a root CA in the VerifyOptions.Roots CertPool, or in the system certificate pool.
How severe is CVE-2026-33810?: CVE-2026-33810 has a CVSS 3.x base score of 8.2, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability none.
Is CVE-2026-33810 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-33810?: CVE-2026-33810 affects Golang Go. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-33810?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-33810 have an EU (EUVD) identifier?: Yes. CVE-2026-33810 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-20024.
When was CVE-2026-33810 published?: CVE-2026-33810 was published on 2026-04-08 and last updated on 2026-07-06.

References

Affected products (1)

cpe:2.3:a:golang:go:*:*:*:*:*:*:*:*

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