How severe is CVE-2020-5203?

CVE-2020-5203 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-2020-5203 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-5203?

CVE-2020-5203 affects Fatfreeframework Fat-free Framework. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-5203?

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.

When was CVE-2020-5203 published?

CVE-2020-5203 was published on 2020-03-11 and last updated on 2026-06-17.

CVE-2020-5203

CVE-2020-5203 is a critical-severity vulnerability in Fatfreeframework Fat-free Framework 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-20.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 2% (80th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Fatfreeframework Fat-free Framework
Published: 2020-03-11
Last modified: 2026-06-17

Description

In Fat-Free Framework 3.7.1, attackers can achieve arbitrary code execution if developers choose to pass user controlled input (e.g., $_REQUEST, $_GET, or $_POST) to the framework's Clear method.

Frequently asked questions

What is CVE-2020-5203?: In Fat-Free Framework 3.7.1, attackers can achieve arbitrary code execution if developers choose to pass user controlled input (e.g., $_REQUEST, $_GET, or $_POST) to the framework's Clear method.
How severe is CVE-2020-5203?: CVE-2020-5203 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-2020-5203 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-5203?: CVE-2020-5203 affects Fatfreeframework Fat-free Framework. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-5203?: 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.
When was CVE-2020-5203 published?: CVE-2020-5203 was published on 2020-03-11 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:fatfreeframework:fat-free_framework:3.7.1:*:*:*:*:*:*:*

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