CVE-2026-111624 json
Umbraco CMS before 17.7.1 and 18.2.1 Missing Authorization on SignalR Hubs
published 24d ago modified 19d ago also EUVD-2026-103046
- cvss
- 3.7
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 23%
- public exploits
- 0
- none known
Summary
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can complete the SignalR negotiate step and receive refreshed notifications that disclose content keys, including unpublished content, and reveal editorial activity timing.
Patch / fix
- umbraco Umbraco-CMS 17.7.1, 18.2.1
Is CVE-2026-111624 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 19d ago
Exploit prediction
0.31% chance of exploitation in the next 30 days, higher than 23% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 6.3 | CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N |
| CNA | 3.1 | 3.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N |
| CNA | 4.0 | 6.3 | CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- umbraco Umbraco-CMS
Classification
- Weakness
-
- CWE-306 Missing Authentication for Critical Functionality
References
-
github.com
/umbraco/Umbraco-CMS/commit/b4f6cfc9d0955f9d8443e68353db4a692e91bd94
patch
-
github.com
/umbraco/Umbraco-CMS/commit/243e082479c777d0f585bbd2f8db571607767b22
patch
-
github.com
/umbraco/Umbraco-CMS/security/advisories/GHSA-4c5q-6c64-96j7
vendor-advisory
-
github.com
/umbraco/Umbraco-CMS/blob/release-18.2.0/src/Umbraco.Cms.Api.Management/Preview/PreviewHub.cs#L9-L11
technical-description
-
github.com
/umbraco/Umbraco-CMS/blob/release-18.2.0/src/Umbraco.Cms.Api.Management/Preview/PreviewHubUpdater.cs#L58
technical-description
-
github.com
/umbraco/Umbraco-CMS/releases/tag/release-18.2.1
release-notes
-
github.com
/umbraco/Umbraco-CMS/releases/tag/release-17.7.1
release-notes
-
vulncheck.com
/advisories/umbraco-cms-before-17.7.1-and-18.2.1-missing-authorization-on-signalr-hubs
third-party-advisory
Sources
- CVE List CVE-2026-111624
- NVD CVE-2026-111624
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.