CVE-2021-29472: Composer's missing argument delimiter can lead to code execution via VCS repository URLs or source download URLs on systems with Mercurial

high Affects composer/composer. Feed 2026.10.29.1, updated 2026-10-28; published 2021-04-29; advisory modified 2026-07-08.

Composer's missing argument delimiter can lead to code execution via VCS repository URLs or source download URLs on systems with Mercurial

Package: composer/composer Composer
Affected versions: <1.10.22 or >=2.0.0-alpha1 and <2.0.13
Fixed in: 1.10.22, 2.0.13
Severity: high CVSS 8.8
Exploitation: not on CISA KEV · EPSS 5% (91.8th percentile)
Published: 2021-04-29
Source: osv.dev

References

CWE-88 CWE-94

NVD record composer/composer advisories

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# PHP projects (recommended)
composer require --dev phpwarden/phpwarden
# then
vendor/bin/phpwarden deps composer.lock

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

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