Denial of Service Vulnerability in Grav Web Platform
CVE-2025-66303

4.9MEDIUM

Key Information:

Vendor

Getgrav

Status
Grav
Vendor
CVE Published:
1 December 2025

What is CVE-2025-66303?

A Denial of Service vulnerability exists in the Grav web platform due to improper sanitization of the 'scheduled_at' parameters used within cron expressions. This flaw allows attackers to disrupt administrative functionalities by introducing malicious input, such as a single quote. As a consequence, the admin panel may become non-functional, impacting operations significantly. Recovery requires manual intervention on the server to amend the 'backup.yaml' file, rectifying the corrupted cron expression. The issue has been addressed in version 1.8.0-beta.27.

Affected Version(s)

grav < 1.8.0-beta.27

References

https://github.com/getgrav/grav/security/advisories/GHSA-...
x_refsource_CONFIRM
https://github.com/getgrav/grav/commit/9d11094e4133f05968...
x_refsource_MISC

CVSS V3.1

Score:
4.9
Severity:
MEDIUM
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
High
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.