How severe is CVE-2020-21005?

CVE-2020-21005 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2020-21005 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-21005?

CVE-2020-21005 affects Wellcms. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-21005?

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

When was CVE-2020-21005 published?

CVE-2020-21005 was published on 2021-06-03 and last updated on 2026-06-17.

CVE-2020-21005

CVE-2020-21005 is a medium-severity vulnerability in Wellcms with a CVSS 3.x base score of 6.5. 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-434.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.0
EPSS exploit prediction: 1% (53rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-434
Affected product: Wellcms
Published: 2021-06-03
Last modified: 2026-06-17

Description

WellCMS 2.0 beta3 is vulnerable to File Upload. A user can log in to the CMS background and upload a picture. Because the upload file type is controllable, the user can modify the upload file type to get webshell.

Frequently asked questions

What is CVE-2020-21005?: WellCMS 2.0 beta3 is vulnerable to File Upload. A user can log in to the CMS background and upload a picture. Because the upload file type is controllable, the user can modify the upload file type to get webshell.
How severe is CVE-2020-21005?: CVE-2020-21005 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2020-21005 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-21005?: CVE-2020-21005 affects Wellcms. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-21005?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-21005 published?: CVE-2020-21005 was published on 2021-06-03 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:wellcms:wellcms:2.0:beta3:*:*:*:*:*:*

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