Umbraco.Engage.Forms Allows Unauthorized Access to Multiple API Endpoints (CVE-2026-27449)
Published Sources: CVE.org, OSV
What is affected, what to do
Umbraco Engage is a business intelligence platform. A vulnerability has been identified in Umbraco Engage prior to versions 16.2.1 and 17.1.1 where certain API endpoints are exposed without enforcing authentication or authorization checks.
Update Umbraco.Engage.Forms to version 16.2.1.
- Affected
- Umbraco.Engage.Forms
gte 17.0.0, < 17.1.1..* - Umbraco.Engage.Forms
lt *..16.2.1
- Umbraco.Engage.Forms
- Fixed in
- Umbraco.Engage.Forms
16.2.1
- Umbraco.Engage.Forms
Not sure whether and how you are affected? Ask a question about this vulnerability
Metrics
7.5
Priority
XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.
Source: Vendor (CNA), CVSS v3
7.5
CVSS v3
Severity High on the scale from 0 to 10.
Source: CVE.org, OSV
0.4 %
EPSS score
Low — model estimates < 1% exploitation likelihood.
Source: FIRST EPSS, percentile 35.1
Show all metrics
- Severity
- High
Priority (0–325)
The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?
Read in glossary- 61.97 Methodology
Exploit maturity
An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.
Read in glossary- no public PoC known
XIEM Effective CVSS
XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command.
Read in glossary- 7.5 Methodology
CVSS v3
CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.
Read in glossary- 7.5
EPSS score
The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“.
Read in glossary- 0.4 %
- Low — model estimates < 1% exploitation likelihood.
EPSS percentile
The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking.
Read in glossary- 35.1
- Elevated — this CVE ranks above at least 10% of all CVEs scored today.
KEV status
The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.
Read in glossary- —
- Published
- CISA assessment (SSVC)
- Exploitation: none known · automatable · Technical impact: partial
- Source: CISA Vulnrichment, as of 3 March 2026
CWE
CWE is a catalogue of typical weakness types in software and hardware — such as flawed input validation, unsafe memory handling or poor authentication. Where a CVE names a concrete vulnerability in a concrete product, a CWE describes the underlying class of defect.
Read in glossary- CWE-284, CWE-306, CWE-639
Detection rules
No NEOSEC detection rule is available for this vulnerability yet.
Classification under NIS2 and CRA
Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.
NIS2
NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.
Read in glossary- High technical severity: assess and remediate the vulnerability in vulnerability handling under Art. 21(2)(e) NIS2 and document the decision.
CRA
The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.
Read in glossary- From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
ISO/IEC 27001
ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.
Read in glossary- Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.
Description
Umbraco Engage is a business intelligence platform. A vulnerability has been identified in Umbraco Engage prior to versions 16.2.1 and 17.1.1 where certain API endpoints are exposed without enforcing authentication or authorization checks. The affected endpoints can be accessed directly over the network without requiring a valid session or user credentials. By supplying a user-controlled identifier parameter (e.g., ?id=), an attacker can retrieve sensitive data associated with arbitrary records. Because no access control validation is performed, the endpoints are vulnerable to enumeration attacks, allowing attackers to iterate over identifiers and extract data at scale. An unauthenticated attacker can retrieve sensitive Engage-related data by directly querying the affected API endpoints. The vulnerability allows arbitrary record access through predictable or enumerable identifiers. The confidentiality impact is considered high. No direct integrity or availability impact has been identified. The scope of exposed data depends on the deployment but may include analytics data, tracking data, customer-related information, or other Engage-managed content. The vulnerability affects both v16 and v17. Patches have already been released. Users are advised to update to 16.2.1 or 17.1.1. No known workarounds are available.
Source: NVD (NIST), OSV (Open Source Vulnerabilities), cvelistv5
Affected products
The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.
| Affected versions | Fixed in | ||
|---|---|---|---|
| umbraco | Umbraco.Engage.Forms |
|
|
| nuget | umbraco.engage.forms |
|
|
Vendors and products
Weakness classes (CWE)
CWE-284Improper Access Control
Pillar
The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.
Entry at MITRE CWE-284CWE-306Missing Authentication for Critical Function
Base
The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.
Entry at MITRE CWE-306CWE-639Authorization Bypass Through User-Controlled Key
Base
The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.
Entry at MITRE CWE-639
References & sources
- github.comumbraco/Umbraco.Engage.Issues/security/advisories/GHSA-86vq-ccw…web, x_refsource_CONFIRM
- NVD (NIST)vuln/detail/CVE-2026-27449advisory
- github.comumbraco/Umbraco.Engage.Issuespackage
Embed badge
Show the severity and KEV status of this vulnerability on your site – with a link back here. The image is updated hourly.
<a href="https://intel.neosec.eu/en/cve/CVE-2026-27449"><img src="https://intel.neosec.eu/badge/cve/CVE-2026-27449.svg?lang=en" alt="CVE-2026-27449 – NEOSEC Intel" height="20"></a>