CVE-2026-56709 (GCVE-0-2026-56709)
Vulnerability from cvelistv5 – Published: 2026-08-25 01:30 – Updated: 2026-08-26 16:12
VLAI
EPSS
VEX
Title
Grav before 3.9.2 Host Header Injection via sendInvitationEmail
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-26 15:58 UTC
CWE
- CWE-350 - Reliance on Reverse DNS Resolution for a Security-Critical Action
Assigner
VulnCheck
CNA
References
2 references
| URL | Tags |
|---|---|
| https://github.com/getgrav/grav/security/advisori… | vendor-advisory |
| https://www.vulncheck.com/advisories/grav-before-… | third-party-advisory |
Impacted products
Date Public
2026-08-10 00:00
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