CVE-2026-79990

GQL entry mutation `siteId` bypasses schema site scope, enabling cross-site content read/write/delete

HIGH
8.7
CVSS Score
Published: September 2, 2026 at 02:19 PM UTC
Updated: September 3, 2026 at 06:04 PM UTC
1 product affected across 1 vendorCraftcms

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Severity
HIGH8.7
Exploit prediction
EPSS 0.4%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

5.0.0-rc1 ≤ v < 5.10.115.0.0-RC1
Affected range stops below 5.10.11, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (4)

Third Party AdvisoryTechnical DescriptionMitigation
Source: cverecord
https://www.hckrt.com/hacktivity/HCKRT-XEQKMX
Product
Source: cverecord
https://github.com/craftcms/cms

SSVC — Action Prioritization

SSVCNo known exploitNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.7HIGHHackrate
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-639

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