CVE-2021-21636: Tfs Missing Permission Check Vulnerability

MODERATE
Advisory Identifier: GHSA-vg28-9f43-gmh5
Share
CVSS 4.3
CWE-862
Published
Advisory Summary

CVE-2021-21636 is a MODERATE (CVSS 4.3) missing permission check vulnerability (CWE-862: Missing Authorization) affecting Tfs libraries in the Maven ecosystem. The issue involves missing permission check in jenkins team foundation server plugin allows enumerating credentials ids. Remediation is available in the latest vendor maintenance releases.

CVE-2021-21636 at a Glance

CVE Identifier CVE-2021-21636
GHSA Identifier GHSA-vg28-9f43-gmh5
Severity MODERATE
CVSS v3.1 Base Score 4.3
CWE Classification CWE-862: Missing Authorization
Affected Product Tfs
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 4.3

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:N/S:U/C:L/I:N/A:N).

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

How to Fix CVE-2021-21636

To remediate this vulnerability, upgrade all affected Tfs 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:tfs fixed: Latest secure release 
<dependency>
    <groupId>org.jenkins-ci.plugins</groupId>
    <artifactId>tfs</artifactId>
    <version>Latest secure release</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-2021-21636, 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 Tfs 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 -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-862: Missing Authorization, where the product does not perform an authorization check when an actor attempts to access a resource or perform an action. In Tfs, 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 Team Foundation Server Plugin 5.157.1 and earlier does not perform a permission check in an HTTP endpoint. This allows attackers with Overall/Read permission to enumerate credentials IDs of credentials stored in Jenkins. Those can be used as part of an attack to capture the credentials using another vulnerability. As of publication of this advisory, there is no fix.

CVE-2021-21636 Affected Tfs Versions

1 component(s)
Product / Package Ecosystem Affected Versions Fixed Version
org.jenkins-ci.plugins:tfs
maven/org.jenkins-ci.plugins/tfs
Maven
≤ 5.157.1

References

NVD — CVE-2021-21636 NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-21636
Tfs Source Repository REPOSITORY
https://github.com/jenkinsci/tfs-plugin
Tfs Security Information SECURITY
https://www.jenkins.io/security/advisory/2021-03-30/#SECURITY-2283%20(1)
Tfs Security Information SECURITY
http://www.openwall.com/lists/oss-security/2021/03/30/1

Frequently Asked Questions

What is CVE-2021-21636?
CVE-2021-21636 is a security vulnerability in Tfs involving Missing permission check in Jenkins Team Foundation Server Plugin allows enumerating credentials IDs under CWE-862: Missing Authorization.
Which Tfs versions are affected?
Affected versions include releases prior to current release patches across affected packages: org.jenkins-ci.plugins:tfs.
What version fixes CVE-2021-21636?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
Is tfs affected?
Yes, org.jenkins-ci.plugins:tfs is affected in releases prior to Latest secure release. Upgrade your dependency to Latest secure release or later.
What is the CVSS score of CVE-2021-21636?
CVE-2021-21636 has a CVSS v3.1 base score of 4.3 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N.
What CWE is associated with CVE-2021-21636?
CVE-2021-21636 is classified under CWE-862: Missing Authorization (The product does not perform an authorization check when an actor attempts to access a resource or perform an action.).
How can I check Maven dependencies for CVE-2021-21636?
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-vg28-9f43-gmh5",
  "modified" : "2023-10-27T14:13:17Z",
  "published" : "2022-05-24T17:45:46Z",
  "aliases" : [ "CVE-2021-21636" ],
  "summary" : "Missing permission check in Jenkins Team Foundation Server Plugin allows enumerating credentials IDs",
  "details" : "Jenkins Team Foundation Server Plugin 5.157.1 and earlier does not perform a permission check in an HTTP endpoint.\n\nThis allows attackers with Overall/Read permission to enumerate credentials IDs of credentials stored in Jenkins. Those can be used as part of an attack to capture the credentials using another vulnerability.\n\nAs of publication of this advisory, there is no fix.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.jenkins-ci.plugins:tfs"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "last_affected" : "5.157.1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-21636"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/jenkinsci/tfs-plugin"
  }, {
    "type" : "WEB",
    "url" : "https://www.jenkins.io/security/advisory/2021-03-30/#SECURITY-2283%20(1)"
  }, {
    "type" : "WEB",
    "url" : "http://www.openwall.com/lists/oss-security/2021/03/30/1"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-862" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2022-12-15T16:59:25Z",
    "nvd_published_at" : "2021-03-30T12:16:00Z"
  }
}