Vulnerability · Published Jun 30, 2026 · Assigned by VulnCheck

CVE-2026-56700Grav - Multiple Remote Code Execution Vulnerabilities via Unsafe Unserialize and Command Injection

Critical 9.8

In plain English

A critical-severity OS command injection in Grav from Grav. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 2.5% (higher than 85% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)9.8Critical

Exploit odds (30 days)2.5%top 15.0% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Packagist	getgrav/grav	2.0.0-beta.2	GHSA-vj3m-2g9h-vm4p

Affected products (as reported)

Vendor	Product	Versions
Grav	Grav	0 – before 2.0.0-beta.2

Weakness: CWE-78, CWE-502 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

GitHub Security Advisory (GHSA-vj3m-2g9h-vm4p) vendor-advisory
VulnCheck Advisory: Grav - Multiple Remote Code Execution Vulnerabilities via Unsafe Unserialize and Command Injection third-party-advisory