CVE-2026-72766: Software Security Vulnerability Vulnerability

HIGH
Advisory Identifier: GHSA-9x27-5f6j-72hw
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CVSS 7.5
CWE-843
Published
Advisory Summary

CVE-2026-72766 is a HIGH (CVSS 7.5) security vulnerability vulnerability (CWE-843: Access of Resource Using Incompatible Type ('Type Confusion')) affecting Software libraries in the Maven ecosystem. The weakness occurs when the product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type.. Remediation is available in the latest vendor maintenance releases.

CVE-2026-72766 at a Glance

CVE Identifier CVE-2026-72766
GHSA Identifier GHSA-9x27-5f6j-72hw
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-843: Access of Resource Using Incompatible Type ('Type Confusion')
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 7.5

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity None (I:N)
Availability None (A:N)

How to Fix CVE-2026-72766

To remediate this vulnerability, upgrade all affected Software dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

mvn dependency:tree

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2026-72766, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree

Analyze the terminal output to locate any version of Software in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than the patched release), your application is affected.

Note: The mvn dependency:tree command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-843: Access of Resource Using Incompatible Type ('Type Confusion'), where the product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type. In Software, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

n8n before 1.123.67, 2.x before 2.31.5, and 2.32.x before 2.32.1 contain a type confusion vulnerability in the Send Email node, which does not enforce that its message fields are strings. A crafted non-string value supplied from a workflow expression into the text or HTML body field can be interpreted by the underlying mail library (Nodemailer) as a file path or URL, allowing arbitrary local file disclosure and server-side request forgery (SSRF). Exploitation requires a pre-existing active workflow with an unauthenticated webhook, valid SMTP credentials configured on the node, and untrusted input mapped directly into the body field; this is not a default configuration.

References

GitHub Advisory / Wiki ADVISORY
https://github.com/n8n-io/n8n/security/advisories/GHSA-2x35-3fw4-9jr4
NVD — CVE-2026-72766 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-72766
www.vulncheck.com/advisories/n8n-befo... WEB
https://www.vulncheck.com/advisories/n8n-before-arbitrary-file-read-via-send-email-node

Frequently Asked Questions

What is CVE-2026-72766?
CVE-2026-72766 is a security vulnerability in Software classified as a security vulnerability vulnerability under CWE-843: Access of Resource Using Incompatible Type ('Type Confusion').
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2026-72766?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2026-72766?
CVE-2026-72766 has a CVSS v3.1 base score of 7.5 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.
What CWE is associated with CVE-2026-72766?
CVE-2026-72766 is classified under CWE-843: Access of Resource Using Incompatible Type ('Type Confusion') (The product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type.).
How can I check Maven dependencies for CVE-2026-72766?
Run the dependency tree command: 'mvn dependency:tree'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-9x27-5f6j-72hw",
  "modified" : "2026-08-28T21:30:33Z",
  "published" : "2026-08-11T15:32:37Z",
  "aliases" : [ "CVE-2026-72766" ],
  "details" : "n8n before 1.123.67, 2.x before 2.31.5, and 2.32.x before 2.32.1 contain a type confusion vulnerability in the Send Email node, which does not enforce that its message fields are strings. A crafted non-string value supplied from a workflow expression into the text or HTML body field can be interpreted by the underlying mail library (Nodemailer) as a file path or URL, allowing arbitrary local file disclosure and server-side request forgery (SSRF). Exploitation requires a pre-existing active workflow with an unauthenticated webhook, valid SMTP credentials configured on the node, and untrusted input mapped directly into the body field; this is not a default configuration.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:L/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" : [ ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/n8n-io/n8n/security/advisories/GHSA-2x35-3fw4-9jr4"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-72766"
  }, {
    "type" : "WEB",
    "url" : "https://www.vulncheck.com/advisories/n8n-before-arbitrary-file-read-via-send-email-node"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-843" ],
    "severity" : "HIGH",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-08-11T13:19:06Z"
  }
}