How severe is CVE-2026-42508?

CVE-2026-42508 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 high, and availability none.

Is CVE-2026-42508 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-42508?

CVE-2026-42508 affects Golang Crypto. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-42508?

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.

Does CVE-2026-42508 have an EU (EUVD) identifier?

Yes. CVE-2026-42508 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31399.

When was CVE-2026-42508 published?

CVE-2026-42508 was published on 2026-05-22 and last updated on 2026-07-08.

CVE-2026-42508

CVE-2026-42508 is a critical-severity vulnerability in Golang Crypto 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-295.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
EPSS exploit prediction: 0% (37th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-31399
Weakness: CWE-295
Affected product: Golang Crypto
Published: 2026-05-22
Last modified: 2026-07-08

Description

Previously, a revoked 'SignatureKey' belonging to a CA was not correctly checked for revocation. Now, both the 'key' and 'key.SignatureKey' are checked for @revoked.

Frequently asked questions

What is CVE-2026-42508?: Previously, a revoked 'SignatureKey' belonging to a CA was not correctly checked for revocation. Now, both the 'key' and 'key.SignatureKey' are checked for @revoked.
How severe is CVE-2026-42508?: CVE-2026-42508 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 high, and availability none.
Is CVE-2026-42508 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-42508?: CVE-2026-42508 affects Golang Crypto. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-42508?: 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.
Does CVE-2026-42508 have an EU (EUVD) identifier?: Yes. CVE-2026-42508 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31399.
When was CVE-2026-42508 published?: CVE-2026-42508 was published on 2026-05-22 and last updated on 2026-07-08.

References

Affected products (1)

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

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