Grav CMS before 2.0.16 contains an origin validation bypass in the Uri::referrer() and Pages::referrerRoute() methods, which validate the Referer header using an unanchored string prefix match (str_starts_with($referrer, $base)) with no trailing delimiter. An attacker who controls a domain that begins with the victim site's origin (e.g. https://example.com.attacker.tld) can send a request with such a Referer to be treated as same-origin, bypassing the Referer-based origin check.
Advisories
Source ID Title
Github GHSA Github GHSA GHSA-9ccq-2jfg-qw33 Grav: Origin validation bypass in Uri::referrer() and Pages::referrerRoute() via unanchored prefix match
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Thu, 08 Oct 2026 17:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Tue, 25 Aug 2026 02:00:00 +0000

Type Values Removed Values Added
Description Grav CMS before 2.0.16 contains an origin validation bypass in the Uri::referrer() and Pages::referrerRoute() methods, which validate the Referer header using an unanchored string prefix match (str_starts_with($referrer, $base)) with no trailing delimiter. An attacker who controls a domain that begins with the victim site's origin (e.g. https://example.com.attacker.tld) can send a request with such a Referer to be treated as same-origin, bypassing the Referer-based origin check.
Title Grav CMS before 2.0.16 Origin Validation Bypass via Referer
First Time appeared Getgrav
Getgrav grav
Weaknesses CWE-346
CPEs cpe:2.3:a:getgrav:grav:*:*:*:*:*:*:*:*
Vendors & Products Getgrav
Getgrav grav
References
Metrics cvssV3_1

{'score': 5.4, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N'}

cvssV4_0

{'score': 9.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-10-08T15:24:25.006Z

Reserved: 2026-08-10T13:02:20.829Z

Link: CVE-2026-72702

cve-icon Vulnrichment

Updated: 2026-08-28T17:52:27.643Z

cve-icon NVD

Status : Deferred

Published: 2026-08-25T02:16:46.120

Modified: 2026-10-08T16:17:34.170

Link: CVE-2026-72702

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-25T05:30:16Z

Weaknesses