CVE-2026-56709 json
Grav before 3.9.2 Host Header Injection via sendInvitationEmail
published 3mo ago modified 30d ago also EUVD-2026-65207 , GHSA-69vf-mjxw-x79j
Unreviewed: the maintainers' own advisory
Published by the maintainers on their GitHub repository getgrav/grav. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 38%
- public exploits
- 0
- none known
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.
Patch / fix
- getgrav grav 3.9.2
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- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 2mo ago
Exploit prediction
0.43% chance of exploitation in the next 30 days, higher than 38% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.7 | 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 |
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
| CNA | 4.0 | 8.7 | 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- getgrav grav
Classification
- Weakness
-
- CWE-350 Reliance on Reverse DNS Resolution for a Security-Critical Action
References
-
github.com
/getgrav/grav/security/advisories/GHSA-69vf-mjxw-x79j
vendor-advisory, advisory
-
vulncheck.com
/advisories/grav-before-host-header-injection-via-sendinvitationemail
third-party-advisory
Sources
- CVE List CVE-2026-56709
- NVD CVE-2026-56709
- Maintainer advisory GHSA-69vf-mjxw-x79j
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
The maintainers of getgrav/grav published their own advisory on GitHub. Reviewed sources take precedence over it.