How severe is CVE-2021-33195?

CVE-2021-33195 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2021-33195 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-33195?

CVE-2021-33195 primarily affects Golang Go. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-33195?

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.

When was CVE-2021-33195 published?

CVE-2021-33195 was published on 2021-08-02 and last updated on 2026-06-17.

CVE-2021-33195

CVE-2021-33195 is a high-severity vulnerability in Golang Go with a CVSS 3.x base score of 7.3. 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-74.

Key facts

Severity: High (CVSS 3.x base score 7.3)
CVSS v2: 7.5
EPSS exploit prediction: 3% (87th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-74
Affected product: Golang Go
Published: 2021-08-02
Last modified: 2026-06-17

Description

Go before 1.15.13 and 1.16.x before 1.16.5 has functions for DNS lookups that do not validate replies from DNS servers, and thus a return value may contain an unsafe injection (e.g., XSS) that does not conform to the RFC1035 format.

Frequently asked questions

What is CVE-2021-33195?: Go before 1.15.13 and 1.16.x before 1.16.5 has functions for DNS lookups that do not validate replies from DNS servers, and thus a return value may contain an unsafe injection (e.g., XSS) that does not conform to the RFC1035 format.
How severe is CVE-2021-33195?: CVE-2021-33195 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2021-33195 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-33195?: CVE-2021-33195 primarily affects Golang Go. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-33195?: 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.
When was CVE-2021-33195 published?: CVE-2021-33195 was published on 2021-08-02 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:golang:go:*:*:*:*:*:*:*:*
cpe:2.3:a:netapp:cloud_insights_telegraf_agent:-:*:*:*:*:*:*:*

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