How severe is CVE-2021-47753?

CVE-2021-47753 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-47753 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-47753?

CVE-2021-47753 affects Phpkf Cms. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-47753?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2021-47753 have an EU (EUVD) identifier?

Yes. CVE-2021-47753 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-2783.

When was CVE-2021-47753 published?

CVE-2021-47753 was published on 2026-01-15 and last updated on 2026-06-17.

CVE-2021-47753

CVE-2021-47753 is a critical-severity vulnerability in Phpkf Cms with a CVSS 3.x base score of 9.8. 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: Critical (CVSS 3.x base score 9.8)
CVSS v4: 9.3
EPSS exploit prediction: 1% (48th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-2783
Weakness: CWE-434
Affected product: Phpkf Cms
Published: 2026-01-15
Last modified: 2026-06-17

Description

phpKF CMS 3.00 Beta y6 contains an unauthenticated file upload vulnerability that allows remote attackers to execute arbitrary code by bypassing file extension checks. Attackers can upload a PHP file disguised as a PNG, rename it, and execute system commands through a crafted web shell parameter.

Frequently asked questions

What is CVE-2021-47753?: phpKF CMS 3.00 Beta y6 contains an unauthenticated file upload vulnerability that allows remote attackers to execute arbitrary code by bypassing file extension checks. Attackers can upload a PHP file disguised as a PNG, rename it, and execute system commands through a crafted web shell parameter.
How severe is CVE-2021-47753?: CVE-2021-47753 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-47753 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-47753?: CVE-2021-47753 affects Phpkf Cms. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-47753?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2021-47753 have an EU (EUVD) identifier?: Yes. CVE-2021-47753 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-2783.
When was CVE-2021-47753 published?: CVE-2021-47753 was published on 2026-01-15 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:phpkf:cms:3.00:beta_y6:*:*:*:*:*:*

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