This affects the package codeception/codeception from 4.0.0 before 4.1.22 and before 3.1.3. The RunProcess class can be leveraged as a gadget to run arbitrary commands on a system that is deserializing user input without validation.
github.com/advisories/GHSA-4574-qv3w-fcmg
github.com/Codeception/Codeception
github.com/Codeception/Codeception/blob/4.1/CHANGELOG-4.x.md#4122
github.com/Codeception/Codeception/blob/4.1/ext/RunProcess.php#L52
github.com/Codeception/Codeception/commit/802a108057d250ee563120eaa5365a519afc0a71
github.com/Codeception/Codeception/commit/cbce9ea7f4664052fa1ac6b36f5b5a6dbd864d71
github.com/Codeception/Codeception/pull/6241
github.com/FriendsOfPHP/security-advisories/blob/master/codeception/codeception/CVE-2021-23420.yaml
github.com/JinYiTong/poc
nvd.nist.gov/vuln/detail/CVE-2021-23420
snyk.io/vuln/SNYK-PHP-CODECEPTIONCODECEPTION-1324585