Vulnerability · Published Oct 14, 2026 · Assigned by VulnCheck
CVE-2026-110765FlexPrice through 2.1.38 QuickBooks Webhook Signature Verification Bypass
Medium 5.9
In plain English
A medium-severity security flaw in flexprice from flexprice. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 13% of all known vulnerabilities).
Severity (CVSS 3.1)5.9Medium
Exploit odds (30 days)0.2%top 86.7% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known
Official description
FlexPrice through 2.1.38 contains an authentication bypass vulnerability in HandleQuickBooksWebhook that skips signature verification when the intuit-signature header is omitted. Unauthenticated attackers knowing a tenant and environment ID can replay forged payment notifications to repeatedly add payment amounts, marking invoices paid or overpaid.
Affected products (as reported)
Weakness: CWE-347 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
References
- https://hackmd.io/@hieuPenguinnn/flexprice-quickbooks-webhook-signature-bypass technical-description, exploit
- https://github.com/flexprice/flexprice/blob/f27da32f84ee34bad4bf39a8d887af87fc3f30fc/internal/api/v1/webhook.go#L750 technical-description
- https://github.com/flexprice/flexprice product
- VulnCheck Advisory: FlexPrice through 2.1.38 QuickBooks Webhook Signature Verification Bypass third-party-advisory