CVE-2026-56709
Published:August 25, 2026
Updated:September 24, 2026
Grav before 3.9.2 fails to validate untrusted Host headers in the sendInvitationEmail() function when constructing token-bearing invitation links. Attackers can manipulate the Host header to poison invitation links and redirect users to attacker-controlled domains, bypassing the require_trusted_host protection which only covers password reset flows.
Affected Packages
https://github.com/getgrav/grav-plugin-login.git (GITHUB):
Affected version(s) >=0.1.0 <3.9.2Fix Suggestion:
Update to version 3.9.2Related Resources (2)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.7
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
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
7.5
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Weakness Type (CWE)
Reliance on Reverse DNS Resolution for a Security-Critical Action
EPSS
Base Score:
0.26