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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-33691 Detail

Description

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 padding in the filename (e.g. photo. php or shell.jsp ). The affected rules do not normalize whitespace before evaluating the file extension regex, so the dot-extension check fails to match. This issue has been patched in versions 3.3.9 and 4.25.0.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
http://seclists.org/fulldisclosure/2026/Apr/0 CVE Mailing List  Third Party Advisory 
http://www.openwall.com/lists/oss-security/2026/03/29/2 CVE Mailing List  Third Party Advisory 
https://github.com/coreruleset/coreruleset/commit/2a8c63512811c5dd74472becebb79a783e68ff02 GitHub, Inc. Patch 
https://github.com/coreruleset/coreruleset/pull/4546 GitHub, Inc. Issue Tracking  Patch 
https://github.com/coreruleset/coreruleset/pull/4547 GitHub, Inc. Issue Tracking  Patch 
https://github.com/coreruleset/coreruleset/pull/4548 GitHub, Inc. Patch 
https://github.com/coreruleset/coreruleset/releases/tag/v3.3.9 GitHub, Inc. Product  Release Notes 
https://github.com/coreruleset/coreruleset/releases/tag/v4.25.0 GitHub, Inc. Product  Release Notes 
https://github.com/coreruleset/coreruleset/security/advisories/GHSA-rw5f-9w43-gv2w GitHub, Inc. Mitigation  Patch  Vendor Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-178 Improper Handling of Case Sensitivity GitHub, Inc.  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

4 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-33691
NVD Published Date:
04/02/2026
NVD Last Modified:
04/07/2026
Source:
GitHub, Inc.