Description
In PHP versions 7.2.x below 7.2.31, 7.3.x below 7.3.18 and 7.4.x below 7.4.6, when HTTP file uploads are allowed, supplying overly long filenames or field names could lead PHP engine to try to allocate oversized memory storage, hit the memory limit and stop processing the request, without cleaning up temporary files created by upload request. This potentially could lead to accumulation of uncleaned temporary files exhausting the disk space on the target server.
Remediation
References
Related Vulnerabilities
WordPress Plugin Anti-Malware Security and Brute-Force Firewall Cross-Site Scripting (4.15.49)
MediaWiki Incorrect Permission Assignment for Critical Resource Vulnerability (CVE-2021-30156)
WordPress Plugin Backlink Rechecker Multiple Cross-Site Scripting Vulnerabilities (1.2.1)
Magento XML Injection (aka Blind XPath Injection) Vulnerability (CVE-2021-21019)