CVE-2026-31867: Craft Commerce has a Potential IDOR in Commerce carts

Severity: medium (CVSS 4.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-03-11 · updated 2026-06-17
Weakness: CWE-639

Description

Craft Commerce is an ecommerce platform for Craft CMS. Prior to 4.11.0 and 5.6.0, An Insecure Direct Object Reference (IDOR) vulnerability exists in Craft Commerce’s cart functionality that allows users to hijack any shopping cart by knowing or guessing its 32-character number. The CartController accepts a user-supplied number parameter to load and modify shopping carts. No ownership validation is performed - the code only checks if the order exists and is incomplete, not whether the requester has authorization to access it. This vulnerability enables the takeover of shopping sessions and potential exposure of PII. This vulnerability is fixed in 4.11.0 and 5.6.0.

Affected products

craftcms commerce: from 4.0.0 before 4.11.0; from 5.0.0 before 5.6.0 — fixed in 4.11.0, 5.6.0

How to fix

Upgrade to a fixed version: craftcms commerce 4.11.0, 5.6.0. Check the vendor advisory for mitigations.

References

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