CVE-2026-79990 GQL entry mutation `siteId` bypasses schema site scope, enabling cross-site content read/write/delete
Attackers with limited site access can read, modify, or delete content in other sites via GraphQL mutations due to missing scope validation.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-79990?
CVE-2026-79990 is a high-severity missing authorization vulnerability in craftcms cms, published on 2 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Craft CMS GraphQL entry mutation resolvers (saveEntry, deleteEntry) read siteIddirectly from$argumentswithout passing throughArgumentManagerprepareArguments(), which is the function that enforces site-scope filtering via array_intersect against the GraphQL schema’s allowed sites. The query path (ElementResolverprepareElementQuery) correctly calls prepareArguments()`, so queries to unauthorized sites return empty. But mutations bypass this entirely — an attacker with a token scoped to Site A can create, modify, or delete entries in Site B by passing siteId in the mutations argument.
Weakness: CWE-639
Which versions are affected by CVE-2026-79990?
How do I fix CVE-2026-79990?
No fix has been published for CVE-2026-79990 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-79990 being exploited?
There is no known exploitation of CVE-2026-79990 in the wild and no public exploit code.
Sources
Also known as GHSA-fvhj-675v-869c.