CVE-2020-36326: Object injection in PHPMailer/PHPMailer

critical Affects phpmailer/phpmailer. Feed 2026.10.29.1, updated 2026-10-28; published 2021-05-04; advisory modified 2026-07-21.

Object injection in PHPMailer/PHPMailer

Package: phpmailer/phpmailer Composer
Affected versions: >=6.1.8 and <6.4.1
Fixed in: 6.4.1
Severity: critical CVSS 9.8
Exploitation: not on CISA KEV · EPSS 3% (87.7th percentile)
Published: 2021-05-04
Source: osv.dev

References

CWE-502 CWE-641

NVD record phpmailer/phpmailer advisories

Am I affected?

Find out in one command. phpwarden checks your composer.lock against this advisory and 20,000+ others, ranked by real-world exploitation (CISA KEV + EPSS). Free, offline, open data.

# PHP projects (recommended)
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# then
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Related advisories

CVE-2016-10033 KEV critical Remote code execution via crafted Sender in the isMail transport same package: phpmailer/phpmailer
CVE-2016-10045 critical Remote code execution in PHPMailer same package: phpmailer/phpmailer
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-2021-34551 high Remote Code Execution vulnerability in PHPMailer 6.4.1 running on Windows same package: phpmailer/phpmailer
CVE-2007-3215 high PHPMailer Shell command injection same package: phpmailer/phpmailer