Umbraco CMS before 17.7.1 and 18.2.1 Missing Authorization on SignalR Hubs
Umbraco CMS before 17.7.1 and 18.2.1 contains a missing authorization vulnerability that allows unauthenticated clients to connect to the backoffice PreviewHub and BackofficeHub SignalR hubs. Attackers can complete the SignalR negotiate step and receive refreshed notifications that disclose content keys, including unpublished content, and reveal editorial activity timing.
CVE-2026-111624
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-111624
Umbraco-CMS
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://github.com/umbraco/Umbraco-CMS",
"vendor": "umbraco",
"product": "Umbraco-CMS",
"versions": [
{
"status": "affected",
"version": "17.0.0",
"lessThan": "17.7.1",
"versionType": "semver"
},
{
"status": "affected",
"version": "18.0.0",
"lessThan": "18.2.1",
"versionType": "semver"
}
],
"packageURL": "pkg:github/umbraco/Umbraco-CMS",
"defaultStatus": "unaffected"
}
]- Related CVEs
- CVE-2026-111624
Source reference:
/cveMetadata/cveId
Publisher severity
medium
Source reference: /containers/cna/metrics
- Event
- #49468 · Revision 1
- Added to Heist Feed
- Publisher date