---
id: CVE-2026-72702
title: >-
  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,
  $base)) with no …
summary: >-
  Grav CMS before 2.0.16 contains an origin validation bypass in the
  Uri::referrer() and Pages::referrerRoute() methods, which validate the Referer
  header using an unanchored string prefix match (str_starts_with($referrer,
  $base)) with no …
severity: medium
cvss: 5.4
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N'
cwe:
  - CWE-346
vendor: getgrav
product: grav
affected:
  - grav < 2.0.16
patched:
  - getgrav/grav 2.0.16
published: '2026-08-25'
updated: '2026-10-12'
sourceUpdated: '2026-10-12T15:10:00.207'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-72702'
references:
  - url: 'https://github.com/getgrav/grav/security/advisories/GHSA-9ccq-2jfg-qw33'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/grav-cms-before-origin-validation-bypass-via-referer
    label: disclosure@vulncheck.com
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-72702'
  - url: 'https://github.com/advisories/GHSA-9ccq-2jfg-qw33'
tags:
  - nvd
  - cve.org
  - exploit-available
  - ghsa
  - composer
epss: 0.00149
epssPercentile: 0.04068
aliases:
  - GHSA-9ccq-2jfg-qw33
ecosystem: composer
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'yes'
  technicalImpact: total
  timestamp: '2026-08-25T16:02:36.978586Z'
ingestedAt: '2026-09-17T20:28:02.779Z'
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Package advisory (CVE-2026-72702)

Affected packages:

- `getgrav/grav <= 2.0.15`

Patched in:

- `getgrav/grav 2.0.16`

Source: https://github.com/advisories/GHSA-9ccq-2jfg-qw33