CVE-2020-2324: Cvs XXE Vulnerability Vulnerability

HIGH
Advisory Identifier: GHSA-g9hg-x9c9-7xgr
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CVSS 7.5
CWE-611
Published
Advisory Summary

CVE-2020-2324 is a HIGH (CVSS 7.5) xxe vulnerability vulnerability (CWE-611: Improper Restriction of XML External Entity Reference) affecting Cvs libraries in the Maven ecosystem. The issue involves xxe vulnerability in jenkins cvs plugin. Remediation is available by upgrading affected packages to version 2.17.

CVE-2020-2324 at a Glance

CVE Identifier CVE-2020-2324
GHSA Identifier GHSA-g9hg-x9c9-7xgr
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-611: Improper Restriction of XML External Entity Reference
Affected Product Cvs
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 7.5

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

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

How to Fix CVE-2020-2324

To remediate this vulnerability, upgrade all affected Cvs 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:cvs fixed: 2.17 
<dependency>
    <groupId>org.jenkins-ci.plugins</groupId>
    <artifactId>cvs</artifactId>
    <version>2.17</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-2020-2324, 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 Cvs in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.17), 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-611: Improper Restriction of XML External Entity Reference, where the product processes an xml document that can contain xml entities with uris that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output. In Cvs, 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 CVS Plugin 2.16 and earlier does not configure its XML parser to prevent XML external entity (XXE) attacks. This allows attackers able to control an agent process to have Jenkins parse a crafted changelog file that uses external entities for extraction of secrets from the Jenkins controller or server-side request forgery. Jenkins CVS Plugin 2.17 disables external entity resolution for its XML parser.

CVE-2020-2324 Affected Cvs Versions

1 component(s)
Fixed Versions:
2.17
Product / Package Ecosystem Affected Versions Fixed Version
org.jenkins-ci.plugins:cvs
maven/org.jenkins-ci.plugins/cvs
Maven
< 2.17
2.17

References

NVD — CVE-2020-2324 NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-2324
Security Fix Commit FIX COMMIT
https://github.com/jenkinsci/cvs-plugin/commit/ff121443b282c8dbd6a5ee4841f152f78e4a5954
Cvs Source Repository REPOSITORY
https://github.com/jenkinsci/cvs-plugin
Cvs Security Information SECURITY
https://www.jenkins.io/security/advisory/2020-12-03/#SECURITY-2146
Cvs Security Information SECURITY
http://www.openwall.com/lists/oss-security/2020/12/03/2

Frequently Asked Questions

What is CVE-2020-2324?
CVE-2020-2324 is a security vulnerability in Cvs involving XXE vulnerability in Jenkins CVS Plugin under CWE-611: Improper Restriction of XML External Entity Reference.
Which Cvs versions are affected?
Affected versions include releases prior to 2.17 across affected packages: org.jenkins-ci.plugins:cvs.
What version fixes CVE-2020-2324?
Upgrading to 2.17 (or the latest patched release for your respective branch) resolves the vulnerability.
Is cvs affected?
Yes, org.jenkins-ci.plugins:cvs is affected in releases prior to 2.17. Upgrade your dependency to 2.17 or later.
What is the CVSS score of CVE-2020-2324?
CVE-2020-2324 has a CVSS v3.1 base score of 7.5 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.
What CWE is associated with CVE-2020-2324?
CVE-2020-2324 is classified under CWE-611: Improper Restriction of XML External Entity Reference (The product processes an XML document that can contain XML entities with URIs that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output.).
How can I check Maven dependencies for CVE-2020-2324?
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-g9hg-x9c9-7xgr",
  "modified" : "2023-10-27T13:17:26Z",
  "published" : "2022-05-24T17:35:09Z",
  "aliases" : [ "CVE-2020-2324" ],
  "summary" : "XXE vulnerability in Jenkins CVS Plugin",
  "details" : "Jenkins CVS Plugin 2.16 and earlier does not configure its XML parser to prevent XML external entity (XXE) attacks.\n\nThis allows attackers able to control an agent process to have Jenkins parse a crafted changelog file that uses external entities for extraction of secrets from the Jenkins controller or server-side request forgery.\n\nJenkins CVS Plugin 2.17 disables external entity resolution for its XML parser.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.jenkins-ci.plugins:cvs"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2.17"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 2.16"
    }
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2020-2324"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/jenkinsci/cvs-plugin/commit/ff121443b282c8dbd6a5ee4841f152f78e4a5954"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/jenkinsci/cvs-plugin"
  }, {
    "type" : "WEB",
    "url" : "https://www.jenkins.io/security/advisory/2020-12-03/#SECURITY-2146"
  }, {
    "type" : "WEB",
    "url" : "http://www.openwall.com/lists/oss-security/2020/12/03/2"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-611" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2022-12-16T22:56:27Z",
    "nvd_published_at" : "2020-12-03T16:15:00Z"
  }
}