CVE-2021-3603
8.1 HIGHPHPMailer 6.4.1 and earlier contain a vulnerability that can result in untrusted code being called (if such code is injected into the hos...
Published: 2021-06-17 · Last updated: 2026-06-17
Severity and scoring
- CVSS
- 8.1 HIGH
- Vector
- CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
- CWE
- CWE-829
Affected products
| Vendor | Product |
|---|---|
| fedoraproject | fedora, phpmailer |
| phpmailer_project | fedora, phpmailer |
Description
PHPMailer 6.4.1 and earlier contain a vulnerability that can result in untrusted code being called (if such code is injected into the host project's scope by other means). If the $patternselect parameter to validateAddress() is set to 'php' (the default, defined by PHPMailer::$validator), and the global namespace contains a function called php, it will be called in preference to the built-in validator of the same name. Mitigated in PHPMailer 6.5.0 by denying the use of simple strings as validator function names.
Source: NVD
References
- [NVD]https://nvd.nist.gov/vuln/detail/CVE-2021-3603
- [Patch]https://github.com/PHPMailer/PHPMailer/commit/45f3c18dc6a2de1cb1bf49b9b249a9ee36a5f7f3
- [Other]https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3YRMWGA4VTMXFB22KICMB7YMFZNFV3EJ/
- [Other]https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FJYSOFCUBS67J3TKR74SD3C454N7VTYM/
- [Other]https://www.huntr.dev/bounties/1-PHPMailer/PHPMailer/
- [Patch]https://github.com/PHPMailer/PHPMailer/commit/45f3c18dc6a2de1cb1bf49b9b249a9ee36a5f7f3
- [Other]https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3YRMWGA4VTMXFB22KICMB7YMFZNFV3EJ/
- [Other]https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FJYSOFCUBS67J3TKR74SD3C454N7VTYM/
- [Other]https://www.huntr.dev/bounties/1-PHPMailer/PHPMailer/
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