CVE-2026-73856
Published:September 30, 2026
Updated:October 01, 2026
libmodsecurity (ModSecurity v3) 3.0.0-rc1 through 3.0.16 matches the response Content-Type against SecResponseBodyMimeType case-sensitively, so a response typed e.g. Text/Html skips response body inspection and all RESPONSE_BODY rules, allowing data leakage those rules would block. Fixed in 3.0.17; ModSecurity v2 lowercases the type and is not affected.
Affected Packages
https://github.com/owasp-modsecurity/ModSecurity.git (GITHUB):
Affected version(s) >=v3.0.0-rc1 <v3.0.17Fix Suggestion:
Update to version v3.0.17Related Resources (2)
Do you need more information?
Contact UsCVSS v4
Base Score:
9.2
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
NONE
Vulnerable System Availability
NONE
Subsequent System Confidentiality
HIGH
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
8.6
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Weakness Type (CWE)
Improper Handling of Case Sensitivity