CVE-2023-0662

A vulnerability was found in PHP. This security flaw occurs when the request body parsing in PHP allows any unauthenticated attacker to consume a large amount of CPU time and trigger excessive logging. A large amount of CPU time required for processing requests can block all available worker processes and significantly delay or slow the processing of legitimate user requests. The large volume of warning messages can wear down the disk and fill it up. A complete denial of service is achievable by sending many concurrent multipart requests in a loop. PHP parses the request body before invoking any application scripts. This vulnerability affects all PHP websites that accept POST request bodies (post_max_size set to a value greater than zero, the default value is 8MB).

Mitigation

Users can decrease the post_max_size close to zero. This will render most websites non-interactive and break file uploads.