CVE-2026-43927

FOSSBilling is a free, open-source billing and client management system. Prior to version 0.8.0, a race condition in the cart checkout flow allows an authenticated client to apply a promo code beyond its configured maximum uses. By sending concurrent checkout requests before any single request completes the usage increment, a client can obtain unlimited discounted or free orders from a single-use or limited-use promo code. Version 0.8.0 patches the issue. Some workarounds are available. Disable promo codes entirely until a patch is available or monitor the `promo` table for `used` values exceeding `maxuses` and manually review affected orders.

CVSS

No CVSS.

References

Link	Resource
https://github.com/FOSSBilling/FOSSBilling/security/advisories/GHSA-w898-cx35-25gh

Configurations

No configuration.

History

06 Jul 2026, 22:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-06 22:16

Updated : 2026-07-07 13:22

NVD link : CVE-2026-43927

Mitre link : CVE-2026-43927

CVE.ORG link : CVE-2026-43927

JSON object : View

Products Affected

No product.

CWE

CWE-367

Time-of-check Time-of-use (TOCTOU) Race Condition

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