CVE-2020-4043
Phar unserialization vulnerability in phpMussel
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
7.7
Phar unserialization vulnerability in phpMussel
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.
- Record
CVE-2020-4043- CVSS 3.1
- 7.7 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N - Weakness
- CWE-502
- Updated
- 2026-11-02
EUVDEUVD-2020-0510
7.7
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.
- Record
EUVD-2020-0510- CVSS 3.1
- 7.7 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-qr95-4mq5-r3fh
7.7
Phar unserialization vulnerability in phpMussel
Impact
What kind of vulnerability is it? Who is impacted?
Anyone using >= v1.0.0 < v1.6.0.
Patches
Has the problem been patched? What versions should users upgrade to?
Yes. Upgrading to at least >= v1.6.0 (the earliest safe version) will resolve the problem. However, as multiple new major versions have been released since that version, upgrading to the latest available version is recommended, in order to protect against any potential future vulnerabilities, unknown at the time of writing this advisory.
Workarounds
Is there a way for users to fix or remediate the vulnerability without upgrading?
Yes. In the package's configuration, disable archive checking by setting check_archives to false (thus avoiding execution of the affected parts of the codebase entirely).
References
Are there any links users can visit to find out more?
Yes. The vulnerability is documented at SECURITY.md and also at #167.
For more information
If you have any questions or comments about this advisory:
- Comment at the issue linked to this advisory, or..
- Contact the package author.
- Record
GHSA-qr95-4mq5-r3fh- CVSS 3.1
- 7.7 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N - Weakness
- CWE-502
- Updated
- 2026-11-02
NVD
7.7
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.
- Record
CVE-2020-4043- CVSS 3.1
- 7.7 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N - CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 7.5 High
AV:N/AC:L/Au:N/C:P/I:P/A:P - Weakness
- CWE-502
- Updated
- 2026-11-02
OSV
9.8
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.
- Record
CVE-2020-4043- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVGHSA-qr95-4mq5-r3fh
7.7
Phar unserialization vulnerability in phpMussel
Impact
What kind of vulnerability is it? Who is impacted?
Anyone using >= v1.0.0 < v1.6.0.
Patches
Has the problem been patched? What versions should users upgrade to?
Yes. Upgrading to at least >= v1.6.0 (the earliest safe version) will resolve the problem. However, as multiple new major versions have been released since that version, upgrading to the latest available version is recommended, in order to protect against any potential future vulnerabilities, unknown at the time of writing this advisory.
Workarounds
Is there a way for users to fix or remediate the vulnerability without upgrading?
Yes. In the package's configuration, disable archive checking by setting check_archives to false (thus avoiding execution of the affected parts of the codebase entirely).
References
Are there any links users can visit to find out more?
Yes. The vulnerability is documented at SECURITY.md and also at #167.
For more information
If you have any questions or comments about this advisory:
- Comment at the issue linked to this advisory, or..
- Contact the package author.
- Record
GHSA-qr95-4mq5-r3fh- CVSS 3.1
- 7.7 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N - Weakness
- CWE-502
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
phpmussel/phpmusselPackagist |
1.0.0 up to 1.6.0 | 1.6.0 |
Maikuolan/phpMusselPackagist |
1.0.0 up to 1.6.0 | 1.6.0 |
phpmussel/phpmusselPackagist |
1.0.0 up to 1.6.0, plus listed versions v1.0.0v1.1.0v1.2.0v1.3.0v1.3.1v1.4.0v1.5.0 |
1.6.0 |
maikuolan/phpmusselPackagist |
1.0.0 up to 1.6.0, plus listed versions v1.0.0v1.1.0v1.2.0v1.3.0v1.3.1v1.4.0v1.5.0 |
1.6.0 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2020-4043 is a high vulnerability (CVSS 7.7) in Phpmussel, published June 10, 2020. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.60%, the 85th percentile. Fixed in phpmussel/phpmussel 1.6.0.
References
github.com/phpMussel/phpMussel/security/advisories/GHSA-qr95-4mq5-r3fh
github.com/phpMussel/phpMussel/issues/167
github.com/phpMussel/phpMussel/pull/173
github.com/phpMussel/phpMussel/commit/97f25973433921c1f953430f32d3081adc4851a4
github.com/phpMussel/phpMussel/security/policy
nvd.nist.gov/vuln/detail/CVE-2020-4043
github.com/advisories/GHSA-qr95-4mq5-r3fh
github.com/phpMussel/phpMussel