Yosemite-Crew: Authorization Bypass Through User-Controlled Key
CVE-2026-59979 is a high-severity authorization bypass through user-controlled key vulnerability in Yosemite-Crew from YosemiteCrew, with a CVSS 3.1 base score of 8.3 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected Yosemite-Crew versions: <= bc1a1824b1a7eba2bc61176cdb61d9a2a11bce57. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.29% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of Yosemite-Crew you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| YosemiteCrew | Yosemite-Crew | <= bc1a1824b1a7eba2bc61176cdb61d9a2a11bce57 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- LowSome restricted data can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:H. Scored by CNA (github.com).
Official description
YosemiteCrew provides organization-based service and task management. In the source-reported affected main and dev snapshots, YosemiteCrew's service and PMS task-library/template routes omit organization and permission checks. `authorizeCognito` in `apps/backend/src/middlewares/auth.ts` sets the authenticated user's ID but does not provide the `withOrgPermissions()` and `requirePermission(...)` checks used by protected siblings. In `apps/backend/src/routers/service.router.ts`, `PATCH /fhir/v1/service/:id` and `DELETE /fhir/v1/service/:id` are authentication-only, while `GET /fhir/v1/service/:id` has no authentication middleware. The trace through `apps/backend/src/controllers/web/service.controller.ts` to `apps/backend/src/services/service.service.ts` passes a global record ID into `ServiceModel.findById(oid)` without an `organisationId` filter. In `apps/backend/src/routers/task.router.ts`, `PUT /v1/task/pms/library/:libraryId`, `POST /v1/task/pms/templates`, `PATCH /v1/task/pms/templates/:templateId` and `DELETE /v1/task/pms/templates/:templateId` likewise lack organization/role enforcement. Any registered platform user, including a patient/companion-app account, can modify or delete another organization's service catalogue and PMS task-library/template data, affecting bookings and billing; service records can additionally be read without authentication. An earlier security change protected create routes but left these sibling operations exposed. A fixed release cannot be established from the available evidence.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Authorization Bypass Through User-Controlled Key
The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.
How developers prevent this class of flaw
- For each and every data access, ensure that the user has sufficient privilege to access the record that is being requested.
- Make sure that the key that is used in the lookup of a specific user's record is not controllable externally by the user or that any tampering can be detected.
- Use encryption in order to make it more difficult to guess other legitimate values of the key or associate a digital signature with the key so that the server can verify that there has been no tampering.
More Authorization Bypass Through User-Controlled Key vulnerabilities (CWE-639)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Recent Authorization Bypass Through User-Controlled Key vulnerabilities
- 8.6 High severity
- 9.1 Critical severity
- 8.5 High severity
- 8.8 High severity
- 7.1 High severity
- 8.8 High severity
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