How severe is CVE-2020-14039?

CVE-2020-14039 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 low, and availability none.

Is CVE-2020-14039 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-14039?

CVE-2020-14039 primarily affects Golang Go. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-14039?

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

When was CVE-2020-14039 published?

CVE-2020-14039 was published on 2020-07-17 and last updated on 2026-06-17.

CVE-2020-14039

CVE-2020-14039 is a medium-severity vulnerability in Golang Go 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-295.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 2% (75th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Golang Go
Published: 2020-07-17
Last modified: 2026-06-17

Description

In Go before 1.13.13 and 1.14.x before 1.14.5, Certificate.Verify may lack a check on the VerifyOptions.KeyUsages EKU requirements (if VerifyOptions.Roots equals nil and the installation is on Windows). Thus, X.509 certificate verification is incomplete.

Frequently asked questions

What is CVE-2020-14039?: In Go before 1.13.13 and 1.14.x before 1.14.5, Certificate.Verify may lack a check on the VerifyOptions.KeyUsages EKU requirements (if VerifyOptions.Roots equals nil and the installation is on Windows). Thus, X.509 certificate verification is incomplete.
How severe is CVE-2020-14039?: CVE-2020-14039 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 low, and availability none.
Is CVE-2020-14039 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-14039?: CVE-2020-14039 primarily affects Golang Go. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-14039?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-14039 published?: CVE-2020-14039 was published on 2020-07-17 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:golang:go:*:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:*

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