CVE-2026-33691 OWASP CRS: Whitespace padding in filenames bypasses file upload extension checks

The OWASP core rule set CRS is a set of generic attack detection rules for use with compatible web application firewalls. Prior to versions 3.3.9 and 4.25.0, a bypass was identified in OWASP CRS that allows uploading files with dangerous extensions .php, .phar, .jsp, .jspx by inserting whitespace...

CVE-2026-33691

The CVE-2026-33691 issue affects OWASP CRS prior to versions 3.3.9 and 4.25.0, where whitespace padding in filenames bypasses the file-extension checks for dangerous extensions (.php, .phar, .jsp, .jspx) because the extension regex is not applied after normalizing whitespace. The vulnerability is...

CVE-2026-21876

The OWASP core rule set CRS is a set of generic attack detection rules for use with compatible web application firewalls. Prior to versions 4.22.0 and 3.3.8, the current rule 922110 has a bug when processing multipart requests with multiple parts. When the first rule in a chain iterates over a...

CVE-2026-21876 OWASP CRS has multipart bypass using multiple content-type parts

The OWASP core rule set CRS is a set of generic attack detection rules for use with compatible web application firewalls. Prior to versions 4.22.0 and 3.3.8, the current rule 922110 has a bug when processing multipart requests with multiple parts. When the first rule in a chain iterates over a...

CVE-2026-21876

The OWASP core rule set CRS is a set of generic attack detection rules for use with compatible web application firewalls. Prior to versions 4.22.0 and 3.3.8, the current rule 922110 has a bug when processing multipart requests with multiple parts. When the first rule in a chain iterates over a...