CVE-2026-72702: Grav CMS before 2.0.16 Origin Validation Bypass via Referer

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-25 · updated 2026-10-12
Weakness: CWE-346

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.

Affected products

getgrav grav: before 2.0.16 — fixed in 2.0.16

How to fix

Upgrade to a fixed version: getgrav grav 2.0.16. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2026-72702 or the next vulnerability affects your stack