Read the docs
TI-2026-40879 Aliases CVE-2026-56700GHSA-58cg-x8gx-6hg3

Grav - Multiple Remote Code Execution Vulnerabilities via Unsafe Unserialize and Command Injection

Priority MEDIUM 53CWE-502Published · Updated

Key facts

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

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-502.

Summary

Grav CMS before 2.0.0-beta.2 contains multiple code-execution vulnerabilities. Three unsafe unserialize() calls - in Scheduler\JobQueue, Framework\Cache\Adapter\FileCache, and Session - deserialize untrusted data without restricting allowed classes, enabling PHP object injection and, via a gadget chain, arbitrary code execution where an attacker controls the serialized input. Additionally, InstallCommand's git clone operation passes the branch, url, and path parameters into a shell command without escaping, allowing OS command injection via plugin/theme installation (which requires admin access). A Twig security blocklist bypass (server-side template injection) is also present. The issues are fixed in 2.0.0-beta.2.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.02528 84th percentileScored 2026-11-07
Fix Fixed Grav (Grav): 2.0.0-beta.2

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Total

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

Affected products

VendorProductAffected versionsFixed inStatusSource
GravGravbefore 2.0.0-beta.22.0.0-beta.2Patch availableCNA
  • Grav VendorGrav Affected before 2.0.0-beta.2 Fixed in 2.0.0-beta.2 Patch available CNA

Remediation

  • Fix · CNA Grav (Grav) Fixed in 2.0.0-beta.2

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-56700
  2. 2026-10-03 Alias added: GHSA-58cg-x8gx-6hg3

References

Advisory 1

  • TI-2026-40880 Grav - XML External Entity Injection via SVG Upload CVSS 4.0HIGH 7.1
  • TI-2026-42219 Grav - Arbitrary File Upload via Avatar Endpoint CVSS 4.0MEDIUM 5.3
  • TI-2026-10325 Stored XSS via missing XSS safety check in Admin2 Pages API partial validation CVSS 4.0MEDIUM 5.1
  • TI-2026-42222 Grav - Stored CSS Injection via Markdown Image resize() Action CVSS 4.0MEDIUM 4.8
  • TI-2026-06424 Grav CMS Cache Value FileCache.php doGet deserialization CVSS 4.0LOW 2.3

Sources

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