Auth bypass in Sylius
CVE-2026-100869
Sylius versions before 2.1.16 and 2.2.9 fail to restrict payment request actions in the Shop API endpoint, allowing customers to trigger refunds on completed orders. Attackers with order tokens can submit arbitrary payment actions like refunds that payment gateways execute while Sylius maintains order as paid, causing financial loss.
Vulnerability class: Broken Access Control
Published .
CVSS v3 metric
CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/Sylius/Sylius (product)
- github.com/Sylius/Sylius/commit/5813831f60f3a60b735a86a57c4b519626a3b75d (patch)
- github.com/Sylius/Sylius/pull/19214 (issue-tracking, patch)
- github.com/Sylius/Sylius/releases/tag/v2.2.9 (release-notes)
- github.com/Sylius/Sylius/security/advisories/GHSA-2rv4-pjmm-7fxf (vendor-advisory)
- www.vulncheck.com/advisories/sylius-2-x-before-2.1.16-and-2.2.9-arbitrary-payme… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-100869?
- CVE-2026-100869 is a medium-severity vulnerability in Sylius, classified under Incorrect Authorization. CVSS score: 5.9/10. Published 2026-09-27.
- How severe is CVE-2026-100869?
- Medium severity. CVSS v3 base score is 5.9 out of 10.