CVE-2026-56709 (GCVE-0-2026-56709)

Vulnerability from cvelistv5 – Published: 2026-08-25 01:30 – Updated: 2026-08-26 16:12
VLAI
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
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
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 under the mitre root
CNA scorecard B 84/100 over 6106 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
getgrav grav Affected: 0 , < 3.9.2 (semver)
Unaffected: 3.9.2 (semver)
    cpe:2.3:a:getgrav:grav:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-08-10 00:00
Credits
alham-rizvi
Show details on NVD website
To clipboard 

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