CVE-2026-56709

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/getgrav/grav/security/advisories/GHSA-69vf-mjxw-x79j
https://www.vulncheck.com/advisories/grav-before-host-header-injection-via-sendinvitationemail

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-25 02:16

Updated : 2026-08-31 20:38

NVD link : CVE-2026-56709

Mitre link : CVE-2026-56709

CVE.ORG link : CVE-2026-56709

JSON object : View

Products Affected

No product.

CWE

CWE-350

Reliance on Reverse DNS Resolution for a Security-Critical Action

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