CVE-2026-42523: Github Cross-Site Scripting Vulnerability

CRITICAL
Advisory Identifier: GHSA-w22p-4x9f-486v
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CVSS 9.0
CWE-79
Published
Advisory Summary

CVE-2026-42523 is a CRITICAL (CVSS 9.0) cross-site scripting vulnerability (CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')) affecting Github libraries in the Maven ecosystem. The issue involves jenkins github plugin has an xss vulnerability. Remediation is available by upgrading affected packages to version 1.46.0.1.

CVE-2026-42523 at a Glance

CVE Identifier CVE-2026-42523
GHSA Identifier GHSA-w22p-4x9f-486v
Severity CRITICAL
CVSS v3.1 Base Score 9.0
CWE Classification CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Affected Product Github
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:L/PR:L/UI:R/S:C/C:H/I:H/A:H).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required Low (PR:L)
User Interaction Required (UI:R)
Scope Changed (S:C)
Confidentiality High (C:H)
Integrity High (I:H)
Availability High (A:H)

How to Fix CVE-2026-42523

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

com.coravy.hudson.plugins.github:github fixed: 1.46.0.1 
<dependency>
    <groupId>com.coravy.hudson.plugins.github</groupId>
    <artifactId>github</artifactId>
    <version>1.46.0.1</version>
</dependency>
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 -Dincludes=com.coravy.hudson.plugins.github

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2026-42523, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree -Dincludes=com.coravy.hudson.plugins.github

Analyze the terminal output to locate any version of Github in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.46.0.1), your application is affected.

Note: The mvn dependency:tree -Dincludes=com.coravy.hudson.plugins.github 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-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting'), where the product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. In Github, 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 Jenkins GitHub Plugin versions 1.46.0 and earlier, the JavaScript that validates the "GitHub hook trigger for GITScm polling" feature improperly processes the current job URL. This results in a stored cross-site scripting (XSS) vulnerability exploitable by non-anonymous attackers with Overall/Read permission. GitHub Plugin 1.46.0.1 no longer processes the current job URL as part of JavaScript implementing validation of the feature "GitHub hook trigger for GITScm polling".

CVE-2026-42523 Affected Github Versions

1 component(s)
Fixed Versions:
1.46.0.1
Product / Package Ecosystem Affected Versions Fixed Version
com.coravy.hudson.plugins.github:github
maven/com.coravy.hudson.plugins.github/github
Maven
< 1.46.0.1
1.46.0.1

References

NVD — CVE-2026-42523 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-42523
Github Source Repository REPOSITORY
https://github.com/jenkinsci/github-plugin
Github Security Information SECURITY
https://www.jenkins.io/security/advisory/2026-04-29/#SECURITY-3704

Frequently Asked Questions

What is CVE-2026-42523?
CVE-2026-42523 is a security vulnerability in Github involving Jenkins GitHub Plugin has an XSS vulnerability under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting').
Which Github versions are affected?
Affected versions include releases prior to 1.46.0.1 across affected packages: com.coravy.hudson.plugins.github:github.
What version fixes CVE-2026-42523?
Upgrading to 1.46.0.1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is github affected?
Yes, com.coravy.hudson.plugins.github:github is affected in releases prior to 1.46.0.1. Upgrade your dependency to 1.46.0.1 or later.
What is the CVSS score of CVE-2026-42523?
CVE-2026-42523 has a CVSS v3.1 base score of 9.0 (CRITICAL) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H.
What CWE is associated with CVE-2026-42523?
CVE-2026-42523 is classified under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') (The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.).
How can I check Maven dependencies for CVE-2026-42523?
Run the dependency tree command: 'mvn dependency:tree -Dincludes=com.coravy.hudson.plugins.github'. 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-w22p-4x9f-486v",
  "modified" : "2026-08-14T19:48:08Z",
  "published" : "2026-04-29T15:30:38Z",
  "aliases" : [ "CVE-2026-42523" ],
  "summary" : "Jenkins GitHub Plugin has an XSS vulnerability",
  "details" : "In Jenkins GitHub Plugin versions 1.46.0 and earlier, the JavaScript that validates the \"GitHub hook trigger for GITScm polling\" feature improperly processes the current job URL.\n\nThis results in a stored cross-site scripting (XSS) vulnerability exploitable by non-anonymous attackers with Overall/Read permission.\n\nGitHub Plugin 1.46.0.1 no longer processes the current job URL as part of JavaScript implementing validation of the feature \"GitHub hook trigger for GITScm polling\".",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "com.coravy.hudson.plugins.github:github"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.46.0.1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-42523"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/jenkinsci/github-plugin"
  }, {
    "type" : "WEB",
    "url" : "https://www.jenkins.io/security/advisory/2026-04-29/#SECURITY-3704"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-79" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-06T22:50:26Z",
    "nvd_published_at" : "2026-04-29T14:16:19Z"
  }
}