What’s Vulnerable › Vulnerabilities

CVE-2026-100872: Sylius 2.x before 2.1.16 and 2.2.9 Payment Amount Overwrite

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-09-27 · updated 2026-09-28
• Weakness: CWE-345

Description

Sylius versions before 2.1.16 and 2.2.9 fail to validate payment amounts during cart recalculation, allowing unauthenticated attackers to modify order totals after gateway transaction initiation. Attackers can pay a small amount, enlarge the order after gateway capture, and have the system mark the inflated order as fully paid while the gateway captured only the original amount.

Affected products

• Sylius: from 2.0.0 before 2.1.16; from 2.2.0 before 2.2.9 — fixed in 2.1.16, 2.2.9

How to fix

Upgrade to a fixed version: Sylius 2.1.16, 2.2.9. Check the vendor advisory for mitigations.

References

• https://github.com/Sylius/Sylius
• https://github.com/Sylius/Sylius/commit/9e9aeaacbc97b1fc01d573e44d6679194527905d
• https://github.com/Sylius/Sylius/pull/19216
• https://github.com/Sylius/Sylius/releases/tag/v2.2.9
• https://github.com/Sylius/Sylius/security/advisories/GHSA-vv4h-q2x8-74g4
• https://www.vulncheck.com/advisories/sylius-2-x-before-2.1.16-and-2.2.9-payment-amount-overwrite
• https://github.com/Sylius/Sylius/security/advisories/GHSA-vv4h-q2x8-74g4

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