CVE-2021-27903: Craft CMS Remote Code Injection

critical Affects craftcms/cms. Feed 2026.10.29.1, updated 2026-10-28; published 2021-07-02; advisory modified 2024-02-16.

Craft CMS Remote Code Injection

Package: craftcms/cms Composer
Affected versions: <3.6.7
Fixed in: 3.6.7
Severity: critical CVSS 9.8
Exploitation: not on CISA KEV · EPSS 3% (86.5th percentile)
Published: 2021-07-02
Source: osv.dev

References

CWE-74 CWE-94

NVD record craftcms/cms 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)
composer require --dev phpwarden/phpwarden
# then
vendor/bin/phpwarden deps composer.lock

# or, without Composer
pipx install phpwarden   &&   phpwarden deps composer.lock

Or keep it checked automatically: GitHub Action · pre-commit hook · GitLab CI · Laravel artisan command

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