CVE-2026-102631: Software Security Vulnerability Vulnerability

MODERATE
Advisory Identifier: GHSA-92hm-xx6p-hch9
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CWE-287
Published
Advisory Summary

CVE-2026-102631 is a MODERATE security vulnerability vulnerability (CWE-287: Improper Authentication) affecting Software libraries in the Maven ecosystem. The weakness occurs when when an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.. Remediation is available in the latest vendor maintenance releases.

CVE-2026-102631 at a Glance

CVE Identifier CVE-2026-102631
GHSA Identifier GHSA-92hm-xx6p-hch9
Severity MODERATE
CVSS v3.1 Base Score N/A
CWE Classification CWE-287: Improper Authentication
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

How to Fix CVE-2026-102631

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-2026-102631, 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-287: Improper Authentication, where when an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. 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 authd before 0.7.1, the user identity matching in UpdateUser (internal/users/manager.go) resolves an incoming login by the broker-scoped provider ID, but falls back to matching the username when the provider ID does not belong to any known user, and does not reject a conflicting non-empty provider ID. If an identity provider reassigns an email address, which authd uses as the username, to a new account, the new account inherits the previous user's local UID and home directory on its next login. This allows the new user to access and modify files belonging to the previous user, including credentials such as SSH keys and cloud API tokens, and silently rebinds the local account record to the new identity. As a mitigation, administrators should lock or delete the previous user's local authd account when the corresponding IdP account is removed.

References

NVD — CVE-2026-102631 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-102631
Software Source Repository REPOSITORY
https://github.com/canonical/authd/pull/2067
bugs.launchpad.net/ubuntu/+source/auth... WEB
https://bugs.launchpad.net/ubuntu/+source/authd/+bug/2168531
Software Security Information SECURITY
https://ubuntu.com/security/CVE-2026-102631

Frequently Asked Questions

What is CVE-2026-102631?
CVE-2026-102631 is a security vulnerability in Software classified as a security vulnerability vulnerability under CWE-287: Improper Authentication.
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2026-102631?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What CWE is associated with CVE-2026-102631?
CVE-2026-102631 is classified under CWE-287: Improper Authentication (When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.).
How can I check Maven dependencies for CVE-2026-102631?
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-92hm-xx6p-hch9",
  "modified" : "2026-10-15T18:32:42Z",
  "published" : "2026-10-15T18:32:42Z",
  "aliases" : [ "CVE-2026-102631" ],
  "details" : "In authd before 0.7.1, the user identity matching in UpdateUser (internal/users/manager.go) resolves an incoming login by the broker-scoped provider ID, but falls back to matching the username when the provider ID does not belong to any known user, and does not reject a conflicting non-empty provider ID. If an identity provider reassigns an email address, which authd uses as the username, to a new account, the new account inherits the previous user's local UID and home directory on its next login. This allows the new user to access and modify files belonging to the previous user, including credentials such as SSH keys and cloud API tokens, and silently rebinds the local account record to the new identity. As a mitigation, administrators should lock or delete the previous user's local authd account when the corresponding IdP account is removed.",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:N/VC:H/VI:L/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-2026-102631"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/canonical/authd/pull/2067"
  }, {
    "type" : "WEB",
    "url" : "https://bugs.launchpad.net/ubuntu/+source/authd/+bug/2168531"
  }, {
    "type" : "WEB",
    "url" : "https://ubuntu.com/security/CVE-2026-102631"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-287" ],
    "severity" : "MODERATE",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-10-15T17:17:10Z"
  }
}