CVE-2021-21618: Repository connector Cross-Site Scripting Vulnerability

MODERATE
Advisory Identifier: GHSA-hg2w-3c4j-jjwm
Share
CVSS 5.4
CWE-79
Published
Advisory Summary

CVE-2021-21618 is a MODERATE (CVSS 5.4) cross-site scripting vulnerability (CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')) affecting Repository connector libraries in the Maven ecosystem. The issue involves stored xss vulnerability in jenkins repository connector plugin. Remediation is available by upgrading affected packages to version 2.0.3.

CVE-2021-21618 at a Glance

CVE Identifier CVE-2021-21618
GHSA Identifier GHSA-hg2w-3c4j-jjwm
Severity MODERATE
CVSS v3.1 Base Score 5.4
CWE Classification CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Affected Product Repository connector
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 5.4

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:L/I:L/A:N).

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 Low (C:L)
Integrity Low (I:L)
Availability None (A:N)

How to Fix CVE-2021-21618

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

org.jenkins-ci.plugins:repository-connector fixed: 2.0.3 
<dependency>
    <groupId>org.jenkins-ci.plugins</groupId>
    <artifactId>repository-connector</artifactId>
    <version>2.0.3</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=org.jenkins-ci.plugins

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2021-21618, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree -Dincludes=org.jenkins-ci.plugins

Analyze the terminal output to locate any version of Repository connector in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.0.3), your application is affected.

Note: The mvn dependency:tree -Dincludes=org.jenkins-ci.plugins 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 Repository connector, 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

Jenkins Repository Connector Plugin 2.0.2 and earlier does not escape parameter names and descriptions for past builds. This results in a stored cross-site scripting (XSS) vulnerability exploitable by attackers with Item/Configure permission. Jenkins Repository Connector Plugin 2.0.3 escapes parameter names and descriptions when creating new parameters.

CVE-2021-21618 Affected Repository connector Versions

1 component(s)
Fixed Versions:
2.0.3
Product / Package Ecosystem Affected Versions Fixed Version
org.jenkins-ci.plugins:repository-connector
maven/org.jenkins-ci.plugins/repository-connector
Maven
< 2.0.3
2.0.3

References

NVD — CVE-2021-21618 NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-21618
Repository connector Source Repository REPOSITORY
https://github.com/jenkinsci/repository-connector-plugin
Repository connector Security Information SECURITY
https://www.jenkins.io/security/advisory/2021-02-24/#SECURITY-2183

Frequently Asked Questions

What is CVE-2021-21618?
CVE-2021-21618 is a security vulnerability in Repository connector involving Stored XSS vulnerability in Jenkins Repository Connector Plugin under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting').
Which Repository connector versions are affected?
Affected versions include releases prior to 2.0.3 across affected packages: org.jenkins-ci.plugins:repository-connector.
What version fixes CVE-2021-21618?
Upgrading to 2.0.3 (or the latest patched release for your respective branch) resolves the vulnerability.
Is repository-connector affected?
Yes, org.jenkins-ci.plugins:repository-connector is affected in releases prior to 2.0.3. Upgrade your dependency to 2.0.3 or later.
What is the CVSS score of CVE-2021-21618?
CVE-2021-21618 has a CVSS v3.1 base score of 5.4 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.
What CWE is associated with CVE-2021-21618?
CVE-2021-21618 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-2021-21618?
Run the dependency tree command: 'mvn dependency:tree -Dincludes=org.jenkins-ci.plugins'. 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-hg2w-3c4j-jjwm",
  "modified" : "2023-10-27T13:29:06Z",
  "published" : "2022-05-24T17:43:00Z",
  "aliases" : [ "CVE-2021-21618" ],
  "summary" : "Stored XSS vulnerability in Jenkins Repository Connector Plugin",
  "details" : "Jenkins Repository Connector Plugin 2.0.2 and earlier does not escape parameter names and descriptions for past builds.\n\nThis results in a stored cross-site scripting (XSS) vulnerability exploitable by attackers with Item/Configure permission.\n\nJenkins Repository Connector Plugin 2.0.3 escapes parameter names and descriptions when creating new parameters.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.jenkins-ci.plugins:repository-connector"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2.0.3"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 2.0.2"
    }
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-21618"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/jenkinsci/repository-connector-plugin"
  }, {
    "type" : "WEB",
    "url" : "https://www.jenkins.io/security/advisory/2021-02-24/#SECURITY-2183"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-79" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2022-12-13T18:55:30Z",
    "nvd_published_at" : "2021-02-24T16:15:00Z"
  }
}