Site Scope Bypass in Craft CMS Affecting GraphQL Entry Mutation Resolvers
CVE-2026-84796

8.7HIGH

Key Information:

Vendor

Craftcms

Status
Cms
Vendor
CVE Published:
2 September 2026

What is CVE-2026-84796?

Craft CMS versions prior to 5.10.11 are vulnerable to a site scope bypass issue within GraphQL entry mutation resolvers. This vulnerability arises from insufficient validation of the siteId parameter within ArgumentManager::prepareArguments(). Consequently, attackers possessing tokens limited to a specific site can exploit this flaw, allowing them to read, modify, or delete entries across unauthorized sites by manipulating the siteId directly in mutation arguments. This poses a significant risk to the integrity and confidentiality of data within Craft CMS.

Affected Version(s)

cms 5.0.0-RC1 < 5.10.11

cms 5.10.11

References

https://github.com/craftcms/cms/security/advisories/GHSA-...
vendor-advisory
https://www.vulncheck.com/advisories/craft-cms-5.0.0-rc1-...
third-party-advisory

CVSS V4

Score:
8.7
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.