CVE-2026-42608
published 2026-05-11CVE-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…
PriorityP182critical9.1CVSS 3.1
AVNACLPRNUINSUCHIHAN
ITWVulnCheck KEV
Exploited in the wild
EPSS
0.52%
43.5th percentile
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.
Affected
4 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| getgrav | grav | < 2.0.0-beta.2 | 2.0.0-beta.2 |
| getgrav | grav | < 2.0.0 | 2.0.0 |
| getgrav | grav | — | — |
| getgrav | grav | >= 0 < 2.0.0-beta.2 | 2.0.0-beta.2 |
CVSS provenance
nvdv3.19.1CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
nvdv4.08.8HIGHCVSS: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/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
vulncheck9.1CRITICAL
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GHSA
Grav has Unauthenticated Path Traversal & Arbitrary File Write in its FormFlash component
ghsa·2026-05-05
CVE-2026-42608 [HIGH] CWE-22 Grav has Unauthenticated Path Traversal & Arbitrary File Write in its FormFlash component
Grav has Unauthenticated Path Traversal & Arbitrary File Write in its FormFlash component
# Vulnerability Report: Grav CMS Unauthenticated Path Traversal & Arbitrary File Write
**[ZERO-DAY] Unauthenticated Path Traversal leading to Arbitrary Directory Creation and Configuration Injection**
## Summary
Grav CMS (v1.7.49.5 and latest development source) is vulnerable to a Zero-Day 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
VulnCheck
getgrav grav Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
vulncheck·2026·CVSS 9.1
CVE-2026-42608 [CRITICAL] getgrav grav Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
getgrav grav Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
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.
Affected: getgrav grav
Required Action: Apply remediations or mitigations per vendor instructions or discontinue use of the prod
No detection rules found.
No public exploits indexed.
2026-05-11
Published
Exploited in the wild