Critical severity · published Jun 30, 2026
CVE-2026-56700
Grav - Multiple Remote Code Execution Vulnerabilities via Unsafe Unserialize and Command Injection
9.8
CVSS
2.5%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.5% · higher than 85% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
GR
Grav · Grav
before 2.0.0-beta.2 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-56700
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-56700
vendor-advisory
https://github.com/getgrav/grav/security/advisories/GHSA-vj3m-2g9h-vm4p
third-party-advisory
https://www.vulncheck.com/advisories/grav-multiple-remote-code-execution-vulnerabilities-via-unsafe-unserialize-and-command-injection
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