Sign in
Deutsch English Español Polski
High

Grav vulnerable to Path traversal / arbitrary YAML write via user creation leading to Account Takeover / System Corruption

  • Disclosed: 02.12.2025
  • Updated: 11.10.2026 10:22

Summary

When a user with privilege of user creation creates a new user through the Admin UI and supplies a username containing path traversal sequences (for example ..\Nijat or ../Nijat), Grav writes the account YAML file to an unintended path outside user/accounts/. The written YAML can contain account fields such as email, fullname, twofa_secret, and hashed_password. In my tests, I was able to cause the Admin UI to write the following content into arbitrary .yaml files (including files like email.yaml, system.yaml, or other site YAML files like admin.yaml) — demonstrating arbitrary YAML write / overwrite via the Admin UI.

Example observed content written by the Admin UI (test data): username: ..\Nijat state: enabled email: EMAIL@gmail.com fullname: 'Nijat Alizada' language: en content_editor: default twofa_enabled: false twofa_secret: RWVEIHC2AFVD6FCR6UHCO3DS4HWXKKDT avatar: { } hashed_password: $2y$10$wl9Ktv3vUmDKCt8o6u2oOuRZr1I04OE0YZf2sJ1QcAherbNnk1XVC access: site: login: true

Steps to Reproduce

  1. Log in to the Grav Admin UI as an administrator.
  2. Create a new user with the following values (example): a. Username: ..\POC-TOKEN-2025-09-29 b. Fullname: POC-TOKEN-2025-09-29 c. Email: poc+2025-09-29@example.test d. Password: (any password) Observe that a YAML file containing the POC-TOKEN is written outside user/accounts/ (for example in the parent directory of user/accounts)

Impact

  1. Config corruption / service disruption: Overwriting system.yaml, email.yaml, or plugin config files with attacker-controlled YAML (even if limited to fields present in account YAML) could break functionality, disable services, or cause misconfiguration requiring recovery from backups.
  2. Account takeover, any user with create user privilege can modify other user's email and password by just creating a new user with the name "..\accounts\USERNAME_OF_VICTIM"

Proof of Concept

https://github.com/user-attachments/assets/cf503d74-f765-4031-8e22-71f6b3630847

Affected software

Click a technology to see all vulnerabilities affecting it.

PlatformPackageVulnerable versionsFixed in
Composer package getgrav/grav < 1.8.0-beta.27 1.8.0-beta.27

References

CVSS score 8.8/10
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE)
CWE-22
Platform
Composer
Package
getgrav/grav
Disclosed
02.12.2025
Updated
11.10.2026 10:22

Sources and licenses

OSV / GitHub Advisory Database - GHSA-h756-wh59-hhjv - CC BY 4.0

Vulnerability history: getgrav/grav

All published vulnerabilities of this package (Composer package), newest first. Shows whether this is a one-off slip or a package that needs watching.

All (99) in the archive
Total entries
99
First → latest
11.2019 09.2026
Without a fix
6
Exploited in attacks
0

Severity breakdown

  • Critical 7
  • High 47
  • Medium 41
  • Low 4

Disclosures per year

Severity:
  1. Grav CMS vulnerable to remote code execution via .zip file upload
    High · 8.8 CVE-2026-72819 < 2.0.13 2.0.13
  2. Grav: Missing admin.super guard on core group blueprint access field allows admin.users operator to escalate to super-admin
    High · 9.1 CVE-2026-75837 < 2.0.14 2.0.14
  3. Grav: Blueprint dynamic-data bare-function branch is denylist-gated and omits error_log, giving arbitrary file write
    Critical · 8.8 CVE-2026-75827 < 2.0.15 2.0.15
  4. Grav: detectXss() misses an event-handler attribute after an unpaired quote in an unquoted attribute value, giving stored XSS
    Critical · 8.7 CVE-2026-75828 < 2.0.15 2.0.15
  5. Grav: Unauthenticated Path Traversal via Missing Directory-Boundary Check in `plugin-asset-map.php` Static Asset Server (`index.php`)
    High · 5.9 CVE-2026-74907 < 2.0.15 2.0.15
  6. Grav: Path Traversal in MediaUploadTrait::deleteFile() Allows Arbitrary File Deletion
    High · 8.1 CVE-2026-72695 < 2.0.16 2.0.16
  7. Grav: media_directory() Twig function allows filesystem path traversal and file content disclosure from sandboxed page content
    High · 6.5 CVE-2026-72697 < 2.0.16 2.0.16
  8. Grav: UserInterface offsetget/offsetexists allow-listed in Twig sandbox let editor-authored content leak hashed_password and 2FA secrets via offsetGet()
    High · 7.7 CVE-2026-76839 < 2.0.16 2.0.16
  9. Grav: config_denied_paths default list omits `system`, exposing real secrets (e.g. system.cache.redis.password) via the Twig sandbox when config_access is enabled
    High · 7.5 CVE-2026-76846 < 2.0.16 2.0.16
  10. Grav: The system, site, and theme Twig variables bypass the content sandbox entirely and are never covered by config_denied_paths
    High · 6.5 CVE-2026-72698 < 2.0.16 2.0.16
  11. Grav: Path Traversal in ImageMedium::watermark() — arbitrary file disclosure via publicly-cached images
    High CVE-2026-69089 >= 2.0.10, < 2.0.11 2.0.11
  12. Grav: Incomplete callable validation in blueprint dynamic fields allows arbitrary static method invocation and file disclosure
    High · 8.1 CVE-2026-69088 >= 2.0.7, < 2.0.11 2.0.11
  13. Grav: FlexDirectory::dynamicDataField() executes arbitrary callables from blueprint data with no validation
    High · 8.8 CVE-2026-65608 >= 1.7.0, < 2.0.9 2.0.9
  14. Grav: 2FA Bypass via 'login.regenerate2FASecret' - Secret Rotation During Pending Challenge
    High · 7.4 CVE-2026-62232 < 2.0.4 2.0.4
  15. Grav: Remote code execution via unrestricted callable in Blueprint::dynamicData()
    High CVE-2026-64850 < 2.0.7 2.0.7
  16. Grav: .htaccess file extension rules bypass via case variation on case-insensitive filesystems
    High CVE-2026-62230 < 2.0.4 2.0.4
  17. Grav: Unauthenticated denial of service via unbounded image derivative dimensions
    High CVE-2026-53653 >= 2.0.0-beta.1, < 2.0.0-rc.8, < 1.7.53 2.0.0-rc.8, 1.7.53
  18. Grav: Twig sandbox allows editor-role users to exfiltrate all plugin secrets via Config::toArray()
    High · 7.7 CVE-2026-44738 < 2.0.0-rc.2 2.0.0-rc.2
  19. Low-privileged Grav API users can create super-admin accounts via blueprint-upload
    High CVE-2026-42844 < 2.0.0-beta.4 2.0.0-beta.4
  20. Grav is Vulnerable to Stored XSS via Tag Injection
    High · 8.9 CVE-2026-42611 < 2.0.0-beta.2 2.0.0-beta.2
  21. Grav has Unauthenticated Path Traversal & Arbitrary File Write in its FormFlash component
    High CVE-2026-42608 < 2.0.0-beta.2 2.0.0-beta.2
  22. Grav Vulnerable to Administrative Account Disruption and Privilege De-escalation via User Overwrite Logic
    High · 8.1 CVE-2026-42609 < 2.0.0-beta.2 2.0.0-beta.2
  23. Grav has multiple RCE vectors: unsafe unserialize (x3), command injection in git clone, SSTI blocklist bypass
    Critical CVE-2026-56700 < 2.0.0-beta.2 2.0.0-beta.2
  24. Grav Vulnerable to Publisher-Level Stored XSS via Unquoted Event Attributes
    High · 8.5 CVE-2026-42612 < 2.0.0-beta.2 2.0.0-beta.2
  25. Grav Vulnerable to Privilege Escalation via Missing Server-Side Validation of groups/access
    Critical · 9.4 CVE-2026-42613 < 2.0.0-beta.2 2.0.0-beta.2
  26. Grav Vulnerable to Remote Code Execution (RCE) via Malicious Plugin ZIP Upload in Direct Install Feature
    Critical · 9.1 CVE-2026-42607 < 2.0.0-beta.2 2.0.0-beta.2
  27. Grav may be vulnerable to SSRF attack via Twig Templates
    Critical · 9.1 CVE-2025-66844 <= 1.7.49.5 no fix
  28. Grav is vulnerable to Server-Side Template Injection (SSTI) via Forms
    High CVE-2025-66298 < 1.8.0-beta.27 1.8.0-beta.27
  29. Grav is vulnerable to RCE via SSTI through Twig Sandbox Bypass
    High CVE-2025-66294 < 1.8.0-beta.27 1.8.0-beta.27
  30. Grav vulnerable to Privilege Escalation and Authenticated Remote Code Execution via Twig Injection
    High CVE-2025-66297 < 1.8.0-beta.27 1.8.0-beta.27
  31. Grav vulnerable to Path traversal / arbitrary YAML write via user creation leading to Account Takeover / System Corruption this entry
    High · 8.8 CVE-2025-66295 < 1.8.0-beta.27 1.8.0-beta.27
  32. Grav vulnerable to Denial of Service via Improper Input Handling in 'Supported' Parameter
    High CVE-2025-66305 < 1.8.0-beta.27 1.8.0-beta.27
  33. Grav has Broken Access Control which allows an Editor to modify the page's YAML Frontmatter to alter form processing actions
    High CVE-2025-66301 < 1.8.0-beta.27 1.8.0-beta.27
  34. Grav is vulnerable to Arbitrary File Read
    High · 8.5 CVE-2025-66300 < 1.8.0-beta.27 1.8.0-beta.27
  35. Grav is Vulnerable to Security Sandbox Bypass with SSTI (Server Side Template Injection)
    High · 8.8 CVE-2025-66299 < 1.8.0-beta.27 1.8.0-beta.27
  36. Grav vulnerable to Privilege Escalation in Grav Admin: Missing Username Uniqueness Check Allows Admin Account Takeover
    High · 8.8 CVE-2025-66296 < 1.8.0-beta.27 1.8.0-beta.27
  37. Grav Vulnerable to Arbitrary File Read to Account Takeover
    High · 8.5 CVE-2024-34082 < 1.7.46 1.7.46
  38. Server Side Template Injection (SSTI) via Twig escape handler
    High · 8.8 CVE-2024-28119 < 1.7.45 1.7.45
  39. Server Side Template Injection (SSTI)
    High · 8.8 CVE-2024-28118 < 1.7.45 1.7.45
  40. Server Side Template Injection (SSTI)
    High · 8.8 CVE-2024-28117 < 1.7.45 1.7.45
  41. Server-Side Template Injection (SSTI) with Grav CMS security sandbox bypass
    High · 8.8 CVE-2024-28116 < 1.7.45 1.7.45
  42. Grav File Upload Path Traversal
    High · 8.8 CVE-2024-27921 < 1.7.45 1.7.45
  43. Remote Code Execution by uploading a phar file using frontmatter
    High · 8.8 CVE-2024-27923 < 1.7.43 1.7.43
  44. grav Server-side Template Injection (SSTI) mitigation bypass
    High · 7.2 CVE-2023-37897 < 1.7.42.2 1.7.42.2
  45. Grav Server-side Template Injection (SSTI) via Twig Default Filters
    High · 7.2 CVE-2023-34448 < 1.7.42 1.7.42
  46. Grav Server-side Template Injection (SSTI) via Denylist Bypass Vulnerability
    High · 7.2 CVE-2023-34253 < 1.7.42 1.7.42
  47. Grav Server-side Template Injection (SSTI) via Twig Default Filters
    High · 7.2 CVE-2023-34252 < 1.7.42 1.7.42
  48. Grav Server Side Template Injection (SSTI) vulnerability
    Critical · 9.1 CVE-2023-34251 < 1.7.42 1.7.42
  49. Code injection in grav
    High · 7.2 CVE-2022-2073 < 1.7.34 1.7.34
  50. Grav CMS Arbitrary File Deletion
    High · 8.1 CVE-2020-29555 >= 1.7.0-beta.1, <= 1.7.0-rc.17, < 1.6.30 1.6.30
  51. Grav CMS Cross-Site Request Forgery (CSRF)
    High · 8.8 CVE-2020-29553 >= 1.7.0-beta.1, <= 1.7.0-rc.17, < 1.6.30 1.6.30
  52. Stored Cross-site Scripting in grav
    High · 7.1 CVE-2022-0970 < 1.7.31 1.7.31
  53. Path traversal in grav
    High · 8.8 CVE-2021-3924 <= 1.7.24 no fix
  54. Grav's Twig processing allowing dangerous PHP functions by default
    High · 8.4 CVE-2021-29440 < 1.7.11 1.7.11

Know which vulnerabilities affect your application

With the DockRay integration and software inventory enabled, DockRay checks reported component versions against known vulnerabilities and notifies you about confirmed matches. Coverage depends on the supported technology and available advisory data.

Connect your application
DockRay newsletter

Application security in your inbox

Important vulnerabilities, actionable guidance and practical advice for your applications. Choose your technologies and follow what matters to your project.

  • A daily digest of new vulnerabilities, critical ones included.
  • Notifications about important updates.
  • Practical advice on application security and monitoring.

Leave empty to receive updates for every technology.

Privacy policy

Free to subscribe. Unsubscribe with one click in any email.