CVE-2026-56700

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.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/getgrav/grav/security/advisories/GHSA-vj3m-2g9h-vm4p
https://www.vulncheck.com/advisories/grav-multiple-remote-code-execution-vulnerabilities-via-unsafe-unserialize-and-command-injection

Configurations

No configuration.

History

30 Jun 2026, 23:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-30 23:17

Updated : 2026-06-30 23:17

NVD link : CVE-2026-56700

Mitre link : CVE-2026-56700

CVE.ORG link : CVE-2026-56700

JSON object : View

Products Affected

No product.

CWE

CWE-78

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

CWE-502

Deserialization of Untrusted Data

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