GHSA-HCPG-PRC4-W26W
Vulnerability from github – Published: 2026-09-23 21:30 – Updated: 2026-09-24 09:31A 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.
{
"affected": [],
"aliases": [
"CVE-2026-84716"
],
"database_specific": {
"cwe_ids": [
"CWE-266"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-09-23T20:17:18Z",
"severity": "MODERATE"
},
"details": "A flaw was found in the automation-controller instance\n install-bundle endpoint. When a System Administrator downloads\n an execution/hop node\u0027s install bundle, the controller signs an\n X.509 certificate with the receptor mesh certificate authority\n in which the Common Name, DNS subject-alternative-name, and\n receptor node-id are taken verbatim from the caller-chosen\n instance hostname, with a hard-coded ten-year validity, a random\n serial, and no issuance log or revocation list. Because the\n hostname charset validator is case-insensitive while the\n uniqueness validator is case-sensitive, an administrator can\n register a case variant of an existing control node\u0027s hostname\n and obtain a mesh-CA-signed certificate that TLS peers, which\n match hostnames case-insensitively, accept as that control node.\n In managed/hosted deployments \u2014 where the customer holds\n controller superuser but the platform operator runs the mesh \u2014\n this yields a long-lived, non-revocable mesh peer credential and,\n with an on-path position, TLS impersonation or interception of\n control/hybrid mesh nodes. It does not grant direct remote code\n execution, because receptor work submission is gated by a\n separate signing key not included in the bundle.",
"id": "GHSA-hcpg-prc4-w26w",
"modified": "2026-09-24T09:31:50Z",
"published": "2026-09-23T21:30:58Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-84716"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2026:71113"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2026:71114"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2026:71177"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2026:71179"
},
{
"type": "WEB",
"url": "https://access.redhat.com/security/cve/CVE-2026-84716"
},
{
"type": "WEB",
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2527199"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:L/A:N",
"type": "CVSS_V3"
}
]
}
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