CVE-2026-42608

Grav is a file-based Web platform. Prior to 2.0.0-beta.2, there is a Path Traversal vulnerability within the FormFlash core component. By manipulating the session_id (passed as __form-flash-id in POST requests), an unauthenticated attacker can traverse the filesystem to create arbitrary directories and write an index.yaml file containing attacker-controlled data. This vulnerability can lead to unauthorized modification of application behavior, potential data integrity issues, and service disruption in production environments. This vulnerability is fixed in 2.0.0-beta.2.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/getgrav/grav/security/advisories/GHSA-hmcx-ch82-3fv2	Exploit Vendor Advisory
https://github.com/getgrav/grav/security/advisories/GHSA-hmcx-ch82-3fv2	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:getgrav:grav::::::::
	cpe:2.3:a:getgrav:grav:2.0.0:beta1::::::

History

No history.

Information

Published : 2026-05-11 16:17

Updated : 2026-06-17 10:48

NVD link : CVE-2026-42608

Mitre link : CVE-2026-42608

CVE.ORG link : CVE-2026-42608

JSON object : View

Products Affected

getgrav

grav

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

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