Sylius vulnerability

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.

Published 27 Sep 2026Updated 27 Sep 20266 sources
CVSS 8.7

What happened

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 versions

Sylius: 2.0.0 through before 2.1.16 (semver); 2.2.0 through before 2.2.9 (semver) Fixed: See vendor advisory.

Why it matters

Review the vendor advisory and exposure of the affected product to determine operational impact.

Detection & mitigation

  • Apply vendor-provided updates or mitigations.
  • Review affected product exposure and access logs.

Public PoC references

No public PoC reference has passed the current publication threshold.