CVE-2024-4577: PHP-CGI argument injection to RCE on Windows via Best-Fit encoding

critical KEV Affects PHP engine. Feed 2026.10.29.1, updated 2026-10-28; published 2024-06-06; listed on CISA KEV 2024-06-12.

PHP-CGI argument injection to RCE on Windows via Best-Fit encoding

Package: PHP engine PHP engine
Affected branches: 8.1 → fixed in 8.1.29; 8.2 → fixed in 8.2.20; 8.3 → fixed in 8.3.8
Severity: critical CVSS 9.8
Exploitation: KEV listed by CISA as actively exploited · ransomware campaigns · EPSS 100% (100.0th percentile)
Remediation: Upgrade to 8.3.8 / 8.2.20 / 8.1.29. Note the follow-up CVE-2024-8926 for non-standard code pages.
Published: 2024-06-06

References

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