CVE-2026-84790: Software Security Vulnerability Vulnerability

HIGH
Advisory Identifier: GHSA-6f9v-9427-9fpm
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CWE-158
Published
Advisory Summary

CVE-2026-84790 is a HIGH security vulnerability vulnerability (CWE-158: Improper Neutralization of Null Byte or NUL Character) affecting Software libraries in the Maven ecosystem. The weakness occurs when the product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes nul characters or null bytes when they are sent to a downstream component.. Remediation is available in the latest vendor maintenance releases.

CVE-2026-84790 at a Glance

CVE Identifier CVE-2026-84790
GHSA Identifier GHSA-6f9v-9427-9fpm
Severity HIGH
CVSS v3.1 Base Score N/A
CWE Classification CWE-158: Improper Neutralization of Null Byte or NUL Character
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

How to Fix CVE-2026-84790

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-2026-84790, 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-158: Improper Neutralization of Null Byte or NUL Character, where the product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes nul characters or null bytes when they are sent to a downstream component. 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

OpenVPN 2.7_alpha1 through 2.7.7 allows remote authenticated users to impersonate others via a crafted certificate subject field

References

NVD — CVE-2026-84790 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-84790
Software Security Information SECURITY
https://community.openvpn.net/Security%20Announcements/CVE-2026-84790

Frequently Asked Questions

What is CVE-2026-84790?
CVE-2026-84790 is a security vulnerability in Software classified as a security vulnerability vulnerability under CWE-158: Improper Neutralization of Null Byte or NUL Character.
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2026-84790?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What CWE is associated with CVE-2026-84790?
CVE-2026-84790 is classified under CWE-158: Improper Neutralization of Null Byte or NUL Character (The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes NUL characters or null bytes when they are sent to a downstream component.).
How can I check Maven dependencies for CVE-2026-84790?
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-6f9v-9427-9fpm",
  "modified" : "2026-10-14T00:31:47Z",
  "published" : "2026-10-14T00:31:47Z",
  "aliases" : [ "CVE-2026-84790" ],
  "details" : "OpenVPN 2.7_alpha1 through 2.7.7 allows remote authenticated users to impersonate others via a crafted certificate subject field",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/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" : [ ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-84790"
  }, {
    "type" : "WEB",
    "url" : "https://community.openvpn.net/Security%20Announcements/CVE-2026-84790"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-158" ],
    "severity" : "HIGH",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-10-13T22:18:58Z"
  }
}