How severe is CVE-2020-4043?

CVE-2020-4043 has a CVSS 3.x base score of 7.7, rated high 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-2020-4043 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-4043?

CVE-2020-4043 affects Phpmussel Project Phpmussel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-4043?

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-2020-4043 published?

CVE-2020-4043 was published on 2020-06-10 and last updated on 2026-06-17.

CVE-2020-4043

CVE-2020-4043 is a high-severity vulnerability in Phpmussel Project Phpmussel with a CVSS 3.x base score of 7.7. 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-502.

Key facts

Severity: High (CVSS 3.x base score 7.7)
CVSS v2: 7.5
EPSS exploit prediction: 3% (83rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-502
Affected product: Phpmussel Project Phpmussel
Published: 2020-06-10
Last modified: 2026-06-17

Description

phpMussel from versions 1.0.0 and less than 1.6.0 has an unserialization vulnerability in PHP's phar wrapper. Uploading a specially crafted file to an affected version allows arbitrary code execution (discovered, tested, and confirmed by myself), so the risk factor should be regarded as very high. Newer phpMussel versions don't use PHP's phar wrapper, and are therefore unaffected. This has been fixed in version 1.6.0.

Frequently asked questions

What is CVE-2020-4043?: phpMussel from versions 1.0.0 and less than 1.6.0 has an unserialization vulnerability in PHP's phar wrapper. Uploading a specially crafted file to an affected version allows arbitrary code execution (discovered, tested, and confirmed by myself), so the risk factor should be regarded as very high. Newer phpMussel versions don't use PHP's phar wrapper, and are therefore unaffected. This has been fixed in version 1.6.0.
How severe is CVE-2020-4043?: CVE-2020-4043 has a CVSS 3.x base score of 7.7, rated high 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-2020-4043 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-4043?: CVE-2020-4043 affects Phpmussel Project Phpmussel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-4043?: 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-2020-4043 published?: CVE-2020-4043 was published on 2020-06-10 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:phpmussel_project:phpmussel:*:*:*:*:*:*:*:*

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