by Kastro
Paper/Archive/CVE-2026-72702

CVE-2026-72702

getgrav grav — Grav CMS before 2.0.16 Origin Validation Bypass via Referer

EPSS 0.1%public exploitCVSS 9.3
critical.is priorityof 100
39
CVSS 9.3 (CNA)9.3 / 10 × 3027.9Not in CISA KEV+300.0EPSS percentile 4.1.041 × 200.8Exploit: SSVC poc+1010.0SSVC exploitation: poc+100.0
Description · from the CVE record

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

ProductAffectedFixed inSource
grav< 2.0.162.0.16CNA

Scores by source

VulnCheck (CNA)9.3CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
VulnCheck (CNA)5.4CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
CISA ADPSSVCExploitation: poc · Automatable: yes · Technical impact: total

References

advisorygithub.com/getgrav/grav/security/advisories/GHSA-9ccq-2jfg-qw33writeupvulncheck.com/advisories/grav-cms-before-origin-validation-bypass-via-referer