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 4.0

9.3CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

CVSS 3.1

9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS

2.5% chance of exploitation in the next 30 days; higher than 84% of CVEs (scores of 2026-10-25)

CWEs

CWE-78, CWE-502

Published

2026-06-30

Modified

2026-10-08

Record from

the NVD, synced 2026-10-19

References

• 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

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