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TI-2026-44526 Aliases CVE-2026-62386GHSA-cx27-6j8x-h4h6

Grav < 1.0.0-rc.16 Authentication Bypass via token URL Parameter

Priority HIGH 75CWE-598Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
High · None · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

The Grav API plugin (getgrav/grav-plugin-api) before 1.0.0-rc.16 accepts JWT access tokens through the ?token= URL query parameter on every API route (JwtAuthenticator::extractBearerToken fallback). Because tokens are embedded in URLs, they are logged verbatim in web server access logs, leaked via the Referer header, stored in browser history, and captured by upstream proxy and CDN logs, exposing valid admin access tokens. A leaked token grants unauthorized API access, including reading configuration and user data, creating admin accounts, modifying system settings, and deleting pages.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00333 26th percentileScored 2026-11-07
Fix Fixed grav (getgrav): 1.0.0-rc.16

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
getgravgravbefore 1.0.0-rc.161.0.0-rc.16Patch availableCNA
  • grav Vendorgetgrav Affected before 1.0.0-rc.16 Fixed in 1.0.0-rc.16 Patch available CNA

Remediation

  • Fix · CNA grav (getgrav) Fixed in 1.0.0-rc.16

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    getgrav grav 1.0.0-rc.16

    2 records Highest priority Priority HIGH 1 HIGH, 1 MEDIUM

    Other records, highest priority first

    • TI-2026-44527 Grav < 1.0.0-rc.16 CORS Misconfiguration via API PluginPriority MEDIUM 64
    Show all 2 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-62386
  2. 2026-10-03 Alias added: GHSA-cx27-6j8x-h4h6

References

Advisory 1

  • TI-2026-30893 Grav: Privilege Escalation via Missing Server-Side Validation of groups/access CVSS 3.1CRITICAL 9.4
  • TI-2025-28971 Cross Site Scripting vulnerability in grav v.1.7.48 and before allows an attacker to… CVSS 3.1CRITICAL 9.8
  • TI-2021-04523 Unauthenticated Arbitrary YAML Write/Update leads to Code Execution CVSS 3.1CRITICAL 9.8
  • TI-2026-50940 Grav CMS before 2.0.16 Origin Validation Bypass via Referer CVSS 4.0CRITICAL 9.3
  • TI-2026-46446 Grav before 2.0.7 Remote Code Execution via Blueprint dynamicData CVSS 4.0CRITICAL 9.3
  • TI-2021-22428 GravCMS 1.10.7 - Arbitrary YAML Write/Update (Unauthenticated) (2) CVSS 4.0CRITICAL 9.3
See all 228 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences