CVE-2021-3603: PHPMailer untrusted code may be run from an overridden address validator

high Affects phpmailer/phpmailer. Feed 2026.10.29.4, updated 2026-10-29; published 2021-06-22; advisory modified 2024-02-17.

PHPMailer untrusted code may be run from an overridden address validator

Package: phpmailer/phpmailer Composer
Affected versions: <6.5.0
Fixed in: 6.5.0
Severity: high CVSS 8.1
Exploitation: not on CISA KEV · EPSS 2% (82.9th percentile)
Published: 2021-06-22
Source: osv.dev

References

CWE-74 CWE-829

NVD record phpmailer/phpmailer advisories

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CVE-2008-5619 high PHPMailer susceptible to arbitrary code execution same package: phpmailer/phpmailer
CVE-2020-13625 high Insufficient output escaping of attachment names in PHPMailer same package: phpmailer/phpmailer
CVE-2020-36326 critical Object injection in PHPMailer/PHPMailer same package: phpmailer/phpmailer
CVE-2021-34551 high Remote Code Execution vulnerability in PHPMailer 6.4.1 running on Windows same package: phpmailer/phpmailer