CVE-2026-42608

Grav: Unauthenticated Path Traversal & Arbitrary File Write in FormFlash component.

Published May 11, 2026 CVSS 4.0 · 8.8 High EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source ID Title
Github GHSA Github GHSA GHSA-hmcx-ch82-3fv2 Grav has Unauthenticated Path Traversal & Arbitrary File Write in its FormFlash component
History
Type Values Removed Values Added
CPEs cpe:2.3:a:getgrav:grav:*:*:*:*:*:*:*:*
cpe:2.3:a:getgrav:grav:2.0.0:beta1:*:*:*:*:*:*
Metrics cvssV3_1

{'score': 9.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N'}

Type Values Removed Values Added
First Time appeared Getgrav
Getgrav grav
Vendors & Products Getgrav
Getgrav grav
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description 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.
Title Grav: Unauthenticated Path Traversal & Arbitrary File Write in FormFlash component.
Weaknesses CWE-22
References
Metrics cvssV4_0

{'score': 8.8, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:P'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
May 11, 2026, 4:07 PM
Reserved
Apr 29, 2026, 12:31 AM
Status
Analyzed
Published
May 11, 2026, 4:17 PM
Modified
Oct 26, 2026, 6:10 PM