How severe is CVE-2021-27919?

CVE-2021-27919 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-27919 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-27919?

CVE-2021-27919 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-2021-27919?

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

When was CVE-2021-27919 published?

CVE-2021-27919 was published on 2021-03-11 and last updated on 2026-06-17.

CVE-2021-27919

CVE-2021-27919 is a medium-severity vulnerability in Golang Go with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 4.3
EPSS exploit prediction: 2% (72nd percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Golang Go
Published: 2021-03-11
Last modified: 2026-06-17

Description

archive/zip in Go 1.16.x before 1.16.1 allows attackers to cause a denial of service (panic) upon attempted use of the Reader.Open API for a ZIP archive in which ../ occurs at the beginning of any filename.

Frequently asked questions

What is CVE-2021-27919?: archive/zip in Go 1.16.x before 1.16.1 allows attackers to cause a denial of service (panic) upon attempted use of the Reader.Open API for a ZIP archive in which ../ occurs at the beginning of any filename.
How severe is CVE-2021-27919?: CVE-2021-27919 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-27919 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-27919?: CVE-2021-27919 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-2021-27919?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-27919 published?: CVE-2021-27919 was published on 2021-03-11 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:golang:go:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*

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