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Medium

Grav is vulnerable to a DOS on the admin panel

  • Disclosed: 02.12.2025
  • Updated: 11.10.2026 10:22

DOS on the admin panel

Severity Rating: Medium

Vector: Denial Of Service

CVE: XXX

CWE: 400 - Uncontrolled Resource Consumption

CVSS Score: 4.9

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H

Analysis

A Denial of Service (DoS) vulnerability has been identified in the application related to the handling of scheduled_at parameters. Specifically, the application fails to properly sanitize input for cron expressions. By manipulating the scheduled_at parameter with a malicious input, such as a single quote, the application admin panel becomes non-functional, causing significant disruptions to administrative operations.

The only way to recover from this issue is to manually access the host server and modify the backup.yaml file to correct the corrupted cron expression

Proof of Concept

  1. Change the value of scheduled_at parameter to ' as shown in the following figures at the http://127.0.0.1/admin/tools endpoint, and observe the response in the second figure: gravdos2 Figure: Http request on tool endpoint gravdos3 Figure: Http response on tool endpoint

  2. When trying to access the admin panel, the panel is broken as shown in the following figure. Additionally, the value change is reflected in the backup.yaml file, as shown in the second figure: gravdos4 Figure: Error message view gravdos5 Figure: Backup.yaml file

Workarounds

No workaround is currently known

Timeline

2024-07-24 Issue identified

2024-09-27 Vendor contacted

About X41 D-Sec GmbH

X41 is an expert provider for application security services. Having extensive industry experience and expertise in the area of information security, a strong core security team of world class security experts enables X41 to perform premium security services.

Fields of expertise in the area of application security are security centered code reviews, binary reverse engineering and vulnerability discovery. Custom research and IT security consulting and support services are core competencies of X41.

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 4.9/10
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE)
CWE-400
Platform
Composer
Package
getgrav/grav
Disclosed
02.12.2025
Updated
11.10.2026 10:22

Sources and licenses

OSV / GitHub Advisory Database - GHSA-x62q-p736-3997 - 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
    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 is vulnerable to a DOS on the admin panel this entry
    Medium · 4.9 CVE-2025-66303 < 1.8.0-beta.27 1.8.0-beta.27
  34. 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
  35. Grav is vulnerable to Arbitrary File Read
    High · 8.5 CVE-2025-66300 < 1.8.0-beta.27 1.8.0-beta.27
  36. 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
  37. 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
  38. Grav Vulnerable to Arbitrary File Read to Account Takeover
    High · 8.5 CVE-2024-34082 < 1.7.46 1.7.46
  39. Server Side Template Injection (SSTI) via Twig escape handler
    High · 8.8 CVE-2024-28119 < 1.7.45 1.7.45
  40. Server Side Template Injection (SSTI)
    High · 8.8 CVE-2024-28118 < 1.7.45 1.7.45
Show more (15) Showing 40 of 55

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