Description
A flaw was found in the automation-controller instance install-bundle endpoint. When a System Administrator downloads an execution/hop node's install bundle, the controller signs an X.509 certificate with the receptor mesh certificate authority in which the Common Name, DNS subject-alternative-name, and receptor node-id are taken verbatim from the caller-chosen instance hostname, with a hard-coded ten-year validity, a random serial, and no issuance log or revocation list. Because the hostname charset validator is case-insensitive while the uniqueness validator is case-sensitive, an administrator can register a case variant of an existing control node's hostname and obtain a mesh-CA-signed certificate that TLS peers, which match hostnames case-insensitively, accept as that control node. In managed/hosted deployments — where the customer holds controller superuser but the platform operator runs the mesh — this yields a long-lived, non-revocable mesh peer credential and, with an on-path position, TLS impersonation or interception of control/hybrid mesh nodes. It does not grant direct remote code execution, because receptor work submission is gated by a separate signing key not included in the bundle.
References6
Metrics
- CVSS 3.1
-
6.6
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:L/A:N - EPSS — exploit probability
- 0% percentile: 7 · as of 9 November 2026
- CWE
- CWE-266
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