How severe is CVE-2021-20671?

CVE-2021-20671 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-20671 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20671?

CVE-2021-20671 affects Weseek Growi. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-20671?

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-2021-20671 published?

CVE-2021-20671 was published on 2021-03-10 and last updated on 2026-06-17.

CVE-2021-20671

CVE-2021-20671 is a high-severity vulnerability in Weseek Growi with a CVSS 3.x base score of 7.2. 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-20.

Key facts

Severity: High (CVSS 3.x base score 7.2)
CVSS v2: 6.5
EPSS exploit prediction: 2% (76th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Weseek Growi
Published: 2021-03-10
Last modified: 2026-06-17

Description

Invalid file validation on the upload feature in GROWI versions v4.2.2 allows a remote attacker with administrative privilege to overwrite the files on the server, which may lead to arbitrary code execution.

Frequently asked questions

What is CVE-2021-20671?: Invalid file validation on the upload feature in GROWI versions v4.2.2 allows a remote attacker with administrative privilege to overwrite the files on the server, which may lead to arbitrary code execution.
How severe is CVE-2021-20671?: CVE-2021-20671 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-20671 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20671?: CVE-2021-20671 affects Weseek Growi. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-20671?: 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-2021-20671 published?: CVE-2021-20671 was published on 2021-03-10 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:weseek:growi:4.2.2:*:*:*:*:*:*:*

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