CVE-2026-42608 (GCVE-0-2026-42608)

Vulnerability from cvelistv5 – Published: 2026-05-11 15:02 – Updated: 2026-05-11 16:07
VLAI Previdian
Title
Grav: Unauthenticated Path Traversal & Arbitrary File Write in FormFlash component.
Summary
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.
Severity
8.8 (High)
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
SSVC
Exploitation: poc Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-11 16:07 UTC
CWE
  • CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7886 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
getgrav grav Affected: < 2.0.0-beta.2
guessed Create a notification for this product.
Previdian
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: e5660d0f-d271-4cdc-a69f-ea42793e2c70

Vulnerability ID: CVE-2026-42608

Status: Confirmed

Status Updated: 2026-09-27 17:12 UTC

Exploited: Yes

Timestamps
First Seen: 2026-09-27
Asserted: 2026-09-27
Scope
Notes: Grav: Unauthenticated Path Traversal & Arbitrary File Write in FormFlash component. | Affected: Getgrav / grav | CVSS: 8.8 (HIGH) | EPSS: 0.00521 | Used in malware: unknown | Not yet in CISA KEV: True
Evidence

Type: Public Report

Signal: Successful Exploitation

Confidence: 70%

Source: previdian

Details
Feed Previdian (previdian.com)
Title Grav: Unauthenticated Path Traversal & Arbitrary File Write in FormFlash component.
Cve Id CVE-2026-42608
Vendor Getgrav
Ghsa Id None
Product grav
Added Date 2026-09-27T17:12:00.000Z
Cvss Score 8.8
Epss Score 0.00521
Previous Ids
Cvss Severity HIGH
Virtual Patch False
Cvss Estimated False
Epss Percentile 0.41948
Used In Malware unknown
Vulnerability Id CVE-2026-42608
Ahead Of Cisa Kev None
Not Yet In Cisa Kev True
References
Created: 2026-09-28 18:00 UTC | Updated: 2026-09-28 18:00 UTC
Show details on NVD website
To clipboard 

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