SB2019070929 - File upload rules bypass in OWASP ModSecurity Core Rule Set (CRS)



SB2019070929 - File upload rules bypass in OWASP ModSecurity Core Rule Set (CRS)

Published: July 9, 2019 Updated: February 9, 2023

Security Bulletin ID SB2019070929
Severity
Medium
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Remote access
Highest impact Data manipulation

Breakdown by Severity

Medium 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 security vulnerability.


1) Input validation error (CVE-ID: CVE-2019-13464)

The vulnerability allows a remote attacker to bypass filtration rules.

The vulnerability exists due to an error when using X.Filename instead of X_Filename in some PHP Script Uploads rules, because PHP automatically transforms dots into underscores in certain contexts where dots are invalid. A remote attacker can bypass implemented rules and successfully upload dangerous files on the server.


Remediation

Install update from vendor's website.