CVE-2020-4043

Name: CVE-2020-4043
Creator: NVD / NIST
Published: 2020-06-10T20:15:14.483+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 2.60%

Last modified Jun 17, 2026

CVE-2020-4043 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. 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. EPSS estimates a 2.60% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

9.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

2.60%

83.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-502

Affected Software

Vendor	Product	Versions
Phpmussel Project	Phpmussel	>= 1.0.0, < 1.6.0

References

https://github.com/phpMussel/phpMussel/commit/97f25973433921c1f953430f32d3081adc4851a4Patch, Release Notes, Third Party Advisory
https://github.com/phpMussel/phpMussel/issues/167Patch, Third Party Advisory
https://github.com/phpMussel/phpMussel/pull/173Patch, Third Party Advisory
https://github.com/phpMussel/phpMussel/security/advisories/GHSA-qr95-4mq5-r3fhMitigation, Third Party Advisory
https://github.com/phpMussel/phpMussel/security/policy#currently-known-vulnerabilitiesThird Party Advisory
https://github.com/phpMussel/phpMussel/commit/97f25973433921c1f953430f32d3081adc4851a4Patch, Release Notes, Third Party Advisory
https://github.com/phpMussel/phpMussel/issues/167Patch, Third Party Advisory
https://github.com/phpMussel/phpMussel/pull/173Patch, Third Party Advisory
https://github.com/phpMussel/phpMussel/security/advisories/GHSA-qr95-4mq5-r3fhMitigation, Third Party Advisory
https://github.com/phpMussel/phpMussel/security/policy#currently-known-vulnerabilitiesThird Party Advisory

Timeline

Published: Jun 10, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-4043?

How severe is CVE-2020-4043?

CVE-2020-4043 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 2.60% probability of exploitation in the next 30 days.

How do I fix CVE-2020-4043?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-4043?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST