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CVE Record

CVE-2026-27449: Umbraco.Engage.Forms Allows Unauthorized Access to Multiple API Endpoints

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.

HighCVSS 7.5Not KEV-listedUpdated
Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

Umbraco Engage Forms has unauthenticated API endpoints in affected 16.x and 17.x versions. An attacker who can reach those endpoints may retrieve sensitive Engage records without logging in. The main business risk is data exposure, potentially including analytics, tracking, customer-related, or other Engage-managed data. Patches are available.

Executive priority

Treat as a high-priority confidentiality issue. Patch affected internet-facing or partner-accessible deployments first, then review logs and data exposure scope. This is not described as destructive, but unauthorized data retrieval at scale is the central concern.

Technical view

CVE-2026-27449 is an access-control failure affecting Umbraco.Engage.Forms before 16.2.1 and 17.1.1. Certain API endpoints do not enforce authentication or authorization. User-controlled record identifiers can be used to access arbitrary records, enabling enumeration. CVSS 3.1 is 7.5 with high confidentiality impact and no identified integrity or availability impact.

Likely exposure

Organizations running Umbraco.Engage.Forms versions below 16.2.1, or 17.0.0 through below 17.1.1, are potentially exposed if the affected APIs are reachable over the network.

Exploitation context

The sources describe unauthenticated network access with low attack complexity and no user interaction. They do not report known active exploitation, and the CVE is not marked in KEV. The practical risk depends on whether affected endpoints are externally reachable and what Engage data exists in the deployment.

Researcher notes

Mapped weaknesses include CWE-284, CWE-306, and CWE-639. The issue is an unauthenticated direct object access pattern across multiple endpoints. Avoid assuming exposed data categories beyond the deployment-specific examples in the advisory. No workaround is identified in the provided sources.

Mitigation direction

  • Upgrade Umbraco.Engage.Forms 16.x deployments to 16.2.1 or later.
  • Upgrade Umbraco.Engage.Forms 17.x deployments to 17.1.1 or later.
  • Review the vendor advisory for any updated guidance.
  • If immediate patching is delayed, restrict network access to Engage API surfaces where feasible.

Validation and detection

  • Inventory all Umbraco Engage deployments and installed Engage Forms versions.
  • Confirm whether any deployment is below 16.2.1 or 17.1.1.
  • Check whether Engage API endpoints are reachable from untrusted networks.
  • Review access logs for unusual unauthenticated requests to Engage API paths.
  • Assess what sensitive Engage-managed data may have been exposed.
Prepared
Confidence
high
Sources
3

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cwe · medium confidence lookup

CWE-284: Authorization and privilege behavior lookup

Authorization weaknesses can support privilege escalation and valid-account review, depending on exploit path. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

Open ATT&CK lookup
cwe · medium confidence lookup

CWE-306: Credential and account abuse lookup

Authentication and credential weaknesses can make valid-account abuse and credential telemetry useful review starting points. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

Open ATT&CK lookup
cwe · low confidence lookup

CWE-639: Exact CWE lookup

Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

Open ATT&CK lookup
cve · low confidence lookup

CVE-2026-27449 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
High
CVSS
7.5 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

1CVSS vectors
0Timeline events
0ADP providers
2Source links

CVSS vector scores

1 official score

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
7.5CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N3.93.6Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

7.5High
CVSS 3.1 vector shape for CVE-2026-27449Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone
Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
umbracoUmbraco.Engage.Forms< 16.2.1, >= 17.0.0, < 17.1.1Listed
Weakness

CWE details

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.