PatchSiren cyber security CVE debrief
CVE-2026-72702 getgrav CVE debrief
The CVE-2026-72702 vulnerability is a critical origin validation bypass in Grav CMS before version 2.0.16. This vulnerability, with a CVSS score of 9.3, allows an attacker controlling a domain that begins with the victim site's origin to bypass the Referer-based origin check by manipulating the Referer header. To verify and mitigate this vulnerability, defenders should review the official CVE Program record and NIST NVD detail page for source-provided CVE metadata and vulnerability assessment. They should also check for patches or updates to Grav CMS, review security configurations, and monitor for suspicious activity. Additionally, defenders should confirm whether affected Grav CMS deployments exist in managed environments, plan vendor-supported updates or mitigations, and review compensating controls for exposed systems. The CVE record was published on 2026-08-25T02:16:46.120Z and has not been modified since then. To ensure comprehensive understanding, security teams should assign an owner for follow-up and track exceptions, retest remediated assets, and close the item only after evidence is documented.
- Vendor
- getgrav
- Product
- grav
- CVSS
- CRITICAL 9.3
- CISA KEV
- Not listed in stored evidence
- Original CVE published
- 2026-08-25
- Original CVE updated
- 2026-08-31
- Advisory published
- 2026-08-25
- Advisory updated
- 2026-08-31
Who should care
Administrators and users of Grav CMS installations, especially those using versions prior to 2.0.16, should be aware of this vulnerability and take necessary actions to mitigate the risk. This includes reviewing and updating security configurations for Grav CMS installations, monitoring for suspicious activity related to Grav CMS, and applying patches or updates to Grav CMS to version 2.0.16 or later. Additionally, security teams and vulnerability management teams should review the official CVE Program record and NIST NVD detail page for source-provided CVE metadata and vulnerability assessment to ensure they have a comprehensive understanding of the vulnerability and its potential impact.
Technical summary
The CVE-2026-72702 vulnerability is caused by an origin validation bypass in the Uri::referrer() and Pages::referrerRoute() methods of Grav CMS before version 2.0.16. This vulnerability allows an attacker who controls a domain that begins with the victim site's origin to send a request with a manipulated Referer header, effectively bypassing the Referer-based origin check. The vulnerability has a CVSS score of 9.3, indicating a critical severity level. Organizations using Grav CMS should prioritize patching to prevent potential origin validation bypass attacks.
Defensive priority
Organizations using Grav CMS should prioritize patching to prevent potential origin validation bypass attacks.
Recommended defensive actions
- Apply patches or updates to Grav CMS to version 2.0.16 or later
- Review and update security configurations for Grav CMS installations
- Monitor for suspicious activity related to Grav CMS
- Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
- Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance
- Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed
- Check relevant monitoring, detection, and logs for exposed assets that need extra review
Evidence notes
The CVE record indicates a critical vulnerability in Grav CMS before version 2.0.16, with a CVSS score of 9.3. The vulnerability is described as an origin validation bypass in the Uri::referrer() and Pages::referrerRoute() methods. The NVD entry is currently Deferred. To verify, defenders should review the official CVE Program record and NIST NVD detail page for source-provided CVE metadata and vulnerability assessment. Additionally, they should check for any available patches or updates to Grav CMS and review security configurations for Grav CMS installations.
Sources and references
Verified primary and authoritative sources
-
CVE-2026-72702 CVE Program record
Publisher, destination, and source semantics verified
URL: https://www.cve.org/CVERecord?id=CVE-2026-72702
CVE Program - Official CVE Program record with source-provided CVE metadata.
-
CVE-2026-72702 NVD vulnerability detail
Publisher, destination, and source semantics verified
URL: https://nvd.nist.gov/vuln/detail/CVE-2026-72702
NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.
Supplemental references
-
Source reference
Unverified legacy reference
URL: https://github.com/getgrav/grav/security/advisories/GHSA-9ccq-2jfg-qw33
-
Source reference
Unverified legacy reference
URL: https://www.vulncheck.com/advisories/grav-cms-before-origin-validation-bypass-via-referer
Methodology and review provenance
AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.