CVE-2026-4408: Software Security Vulnerability Vulnerability

CRITICAL
Advisory Identifier: GHSA-jg8v-92xc-cx65
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CVSS 9.0
CWE-78
Published
Advisory Summary

CVE-2026-4408 is a CRITICAL (CVSS 9.0) security vulnerability vulnerability (CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')) affecting Software libraries in the Maven ecosystem. The weakness occurs when the product constructs all or part of an os command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended os command when it is sent to a downstream component.. Remediation is available in the latest vendor maintenance releases.

CVE-2026-4408 at a Glance

CVE Identifier CVE-2026-4408
GHSA Identifier GHSA-jg8v-92xc-cx65
Severity CRITICAL
CVSS v3.1 Base Score 9.0
CWE Classification CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 9.0

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

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

How to Fix CVE-2026-4408

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-2026-4408, 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-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection'), where the product constructs all or part of an os command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended os command when it is 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

A flaw was found in Samba. A remote attacker can exploit a misconfiguration in Samba file servers and classic domain controllers that use the "check password script" feature. If this script is configured with the %u substitution character, the client-controlled username is passed without proper escaping of shell meta-characters. This vulnerability allows an attacker to achieve remote command execution on the affected system. This issue primarily affects non-standard configurations where the "check password script" is used with %u and the samba-dcerpcd service is started as a system service.

References

NVD — CVE-2026-4408 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-4408
Software Security Information SECURITY
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4408.json
bugzilla.samba.org/show_bug.cgi WEB
https://bugzilla.samba.org/show_bug.cgi?id=16034
bugzilla.redhat.com/show_bug.cgi WEB
https://bugzilla.redhat.com/show_bug.cgi?id=2479762
Software Security Information SECURITY
https://access.redhat.com/security/cve/CVE-2026-4408
access.redhat.com/errata/rhsa-2026:65... WEB
https://access.redhat.com/errata/RHSA-2026:65839
access.redhat.com/errata/rhsa-2026:60... WEB
https://access.redhat.com/errata/RHSA-2026:60019
access.redhat.com/errata/rhsa-2026:59... WEB
https://access.redhat.com/errata/RHSA-2026:59831
access.redhat.com/errata/rhsa-2026:57... WEB
https://access.redhat.com/errata/RHSA-2026:57483
access.redhat.com/errata/rhsa-2026:56... WEB
https://access.redhat.com/errata/RHSA-2026:56911
access.redhat.com/errata/rhsa-2026:56... WEB
https://access.redhat.com/errata/RHSA-2026:56853
access.redhat.com/errata/rhsa-2026:56... WEB
https://access.redhat.com/errata/RHSA-2026:56786
access.redhat.com/errata/rhsa-2026:29... WEB
https://access.redhat.com/errata/RHSA-2026:29863
access.redhat.com/errata/rhsa-2026:29... WEB
https://access.redhat.com/errata/RHSA-2026:29833
access.redhat.com/errata/rhsa-2026:29... WEB
https://access.redhat.com/errata/RHSA-2026:29799
access.redhat.com/errata/rhsa-2026:28... WEB
https://access.redhat.com/errata/RHSA-2026:28132
access.redhat.com/errata/rhsa-2026:28... WEB
https://access.redhat.com/errata/RHSA-2026:28058
access.redhat.com/errata/rhsa-2026:28... WEB
https://access.redhat.com/errata/RHSA-2026:28057
access.redhat.com/errata/rhsa-2026:28... WEB
https://access.redhat.com/errata/RHSA-2026:28056
access.redhat.com/errata/rhsa-2026:28... WEB
https://access.redhat.com/errata/RHSA-2026:28055
access.redhat.com/errata/rhsa-2026:28... WEB
https://access.redhat.com/errata/RHSA-2026:28054
access.redhat.com/errata/rhsa-2026:28... WEB
https://access.redhat.com/errata/RHSA-2026:28053
access.redhat.com/errata/rhsa-2026:25... WEB
https://access.redhat.com/errata/RHSA-2026:25979
access.redhat.com/errata/rhsa-2026:25... WEB
https://access.redhat.com/errata/RHSA-2026:25049
access.redhat.com/errata/rhsa-2026:22... WEB
https://access.redhat.com/errata/RHSA-2026:22963
access.redhat.com/errata/rhsa-2026:22... WEB
https://access.redhat.com/errata/RHSA-2026:22644

Frequently Asked Questions

What is CVE-2026-4408?
CVE-2026-4408 is a security vulnerability in Software classified as a security vulnerability vulnerability under CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection').
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2026-4408?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2026-4408?
CVE-2026-4408 has a CVSS v3.1 base score of 9.0 (CRITICAL) with vector string CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H.
What CWE is associated with CVE-2026-4408?
CVE-2026-4408 is classified under CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') (The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.).
How can I check Maven dependencies for CVE-2026-4408?
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 
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  } ],
  "database_specific" : {
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    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-05-28T09:16:47Z"
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}