CVE-2026-75827 getgrav CVE debrief

Who should care

Defenders responsible for Grav installations, particularly those with page-edit or blueprint-config access, should assess exposure and prioritize remediation. This includes reviewing and applying patches, restricting access to vulnerable features, and verifying Grav version and patch application. Security teams and vulnerability management teams should also be aware of the potential impacts and take necessary actions.

Why it matters

CVE-2026-75827 is a critical vulnerability in Grav that allows remote code execution. Defenders should prioritize patching and restrict access to vulnerable features.

• Remote code execution is possible for attackers with page-edit or blueprint-config access.
• Web-accessible files can be modified without authorization.
• Verification of Grav version and patch application is necessary.
• Restrictive access controls for page-edit and blueprint-config features are required.

Technical summary

CVE-2026-75827 is an arbitrary file write vulnerability in Grav before 2.0.15. The vulnerability exists in the Blueprint dynamic-data bare-function validation, which uses an incomplete denylist instead of a positive allowlist. Attackers with page-edit or blueprint-config access can invoke the error_log function through a data directive to append PHP payloads to web-accessible files, achieving remote code execution.

Defensive priority

High

Recommended defensive actions

• Review and apply the vendor's official patches or updates.
• Restrict access to page-edit and blueprint-config features.
• Monitor web-accessible files for unauthorized modifications.
• Verify the integrity of Grav installations.
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.
• 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.

Evidence notes

The CVE record and NVD entry provide details on the vulnerability. However, the scope of affected versions and remediation steps require verification from official sources. The CVE Program record (CVE-2026-75827) and NVD entry offer source-provided CVE metadata and official vulnerability details. Additional verification is necessary to confirm affected scope, severity, and vendor guidance.

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.