CVE-2026-54431: Software Security Vulnerability Vulnerability

MODERATE
Advisory Identifier: GHSA-3pf6-g4x4-jm46
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CWE-358
Published
Advisory Summary

CVE-2026-54431 is a MODERATE security vulnerability vulnerability (CWE-358: Improperly Implemented Security Check for Standard) affecting Software libraries in the Maven ecosystem. The weakness occurs when the product does not implement or incorrectly implements one or more security-relevant checks as specified by the design of a standardized algorithm, protocol, or technique.. Remediation is available in the latest vendor maintenance releases.

CVE-2026-54431 at a Glance

CVE Identifier CVE-2026-54431
GHSA Identifier GHSA-3pf6-g4x4-jm46
Severity MODERATE
CVSS v3.1 Base Score N/A
CWE Classification CWE-358: Improperly Implemented Security Check for Standard
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

How to Fix CVE-2026-54431

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-2026-54431, 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-358: Improperly Implemented Security Check for Standard, where the product does not implement or incorrectly implements one or more security-relevant checks as specified by the design of a standardized algorithm, protocol, or technique. 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

In liboauth2 the Demonstrating Proof-of-Possession (DPoP) verifier accepts a proof whose JSON Web Key (jwk) header contains private key material. RFC 9449 section 4.3 step 7 requires the verifier to reject such a proof but oauth2_token_verify() function returns success for a malformed DPoP proof that embeds the private Elliptic Curve (EC) key in the header. This issue was fixed in version 2.3.0

References

NVD — CVE-2026-54431 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-54431
Security Fix Commit FIX COMMIT
https://github.com/OpenIDC/liboauth2/commit/c0b57152ed6a0af33aeb04a60bd7f5bff5ab8800
cert.pl/en/posts/2026/07/cv... WEB
https://cert.pl/en/posts/2026/07/CVE-2026-54430
Software Source Repository REPOSITORY
https://github.com/OpenIDC/liboauth2

Frequently Asked Questions

What is CVE-2026-54431?
CVE-2026-54431 is a security vulnerability in Software classified as a security vulnerability vulnerability under CWE-358: Improperly Implemented Security Check for Standard.
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2026-54431?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What CWE is associated with CVE-2026-54431?
CVE-2026-54431 is classified under CWE-358: Improperly Implemented Security Check for Standard (The product does not implement or incorrectly implements one or more security-relevant checks as specified by the design of a standardized algorithm, protocol, or technique.).
How can I check Maven dependencies for CVE-2026-54431?
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-3pf6-g4x4-jm46",
  "modified" : "2026-07-02T12:30:59Z",
  "published" : "2026-07-02T12:30:59Z",
  "aliases" : [ "CVE-2026-54431" ],
  "details" : "In liboauth2 the Demonstrating Proof-of-Possession (DPoP) verifier accepts a proof whose JSON Web Key (jwk) header contains private key material. RFC 9449 section 4.3 step 7 requires the verifier to reject such a proof but oauth2_token_verify() function returns success for a malformed DPoP proof that embeds the private Elliptic Curve (EC) key in the header.\n\nThis issue was fixed in version 2.3.0",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/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-2026-54431"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/OpenIDC/liboauth2/commit/c0b57152ed6a0af33aeb04a60bd7f5bff5ab8800"
  }, {
    "type" : "WEB",
    "url" : "https://cert.pl/en/posts/2026/07/CVE-2026-54430"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/OpenIDC/liboauth2"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-358" ],
    "severity" : "MODERATE",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-07-02T11:16:17Z"
  }
}