CVE-2026-78851 Grav CVE debrief

Who should care

Defenders responsible for Grav CMS installations should assess exposure and prioritize verification of their versions. This includes operators, platform administrators, vulnerability management teams, and security teams. They should verify if their Grav CMS versions 2.0.3 through 2.0.6 are in use and assess the need for an update.

Why it matters

CVE-2026-78851 is a Directory Traversal vulnerability in Grav CMS 2.0.3 through 2.0.6 that allows remote attackers to obtain sensitive information. Defenders should assess exposure, prioritize verification, and verify vendor remediation.

• Verify potential directory traversal attempts
• Assess the need for an update to prevent information disclosure

Technical summary

A Directory Traversal vulnerability exists in Grav CMS versions 2.0.3 through 2.0.6. The vulnerability is located in the GravExtension.php and the mediaDirFunc method, allowing remote attackers to obtain sensitive information. This vulnerability allows attackers to access sensitive information by traversing the directory structure. Defenders should assess exposure and prioritize verification of their versions. The CVE record and source item provide limited information about the vulnerability. Defenders should review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance.

Defensive priority

Defenders should verify if their Grav CMS versions 2.0.3 through 2.0.6 are in use and assess the need for an update.

Recommended defensive actions

• Verify if Grav CMS versions 2.0.3 through 2.0.6 are in use
• Assess the need for an update
• Monitor for potential directory traversal attempts
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record and source item provide limited information about the vulnerability. The NVD entry is currently empty. Defenders should verify if their Grav CMS versions 2.0.3 through 2.0.6 are in use and assess the need for an update. The vulnerability allows remote attackers to obtain sensitive information via the GravExtension.php and the mediaDirFunc method.

Sources and references

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.