SB2019070929 - File upload rules bypass in OWASP ModSecurity Core Rule Set (CRS)
Published: July 9, 2019 Updated: February 9, 2023
Security Bulletin ID
SB2019070929
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Data manipulation
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Input validation error (CVE-ID: CVE-2019-13464)
CWE-ID: CWE-20 - Improper input validation
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
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.