CVE-2026-93854
UnratedPublished 2026-09-18 ยท last changed 2026-09-18
The fix
We hold no Microsoft remediation data for CVE-2026-93854, which normally means it is not a Windows CVE. For non-Microsoft software the fix is the vendor's own updated release, and the affected versions are listed below.
What it is
In OpenStack Blazar before 17.0.1, the V2 lease API does not enforce object-level authorization on its update and delete operations (PUT /v2/leases/{lease_id} and DELETE /v2/leases/{lease_id}). The policy authorize() wrapper attempts to load the target lease to build the authorization target from its owner, but it looks up the lease under the keyword "lease_id" whereas the controller methods name the parameter "id" (and the wsme_pecan.wsexpose wrapper delivers it positionally). The lookup returns None, and thus authorization falls back to the requesting user's own project_id/user_id instead of the target lease owner. Any authenticated user who knows a lease ID can therefore modify or delete leases belonging to other users and projects, bypassing the intended ownership check.