CVE-2020-2091: Ec2 Missing Permission Checks Vulnerability

MODERATE
Advisory Identifier: GHSA-6hmm-77r2-h6hr
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CVSS 5.0
CWE-862
Published
Advisory Summary

CVE-2020-2091 is a MODERATE (CVSS 5.0) missing permission checks vulnerability (CWE-862: Missing Authorization) affecting Ec2 libraries in the Maven ecosystem. The issue involves missing permission checks in jenkins amazon ec2 plugin. Remediation is available by upgrading affected packages to version 1.48.

CVE-2020-2091 at a Glance

CVE Identifier CVE-2020-2091
GHSA Identifier GHSA-6hmm-77r2-h6hr
Severity MODERATE
CVSS v3.1 Base Score 5.0
CWE Classification CWE-862: Missing Authorization
Affected Product Ec2
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 5.0

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

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

How to Fix CVE-2020-2091

To remediate this vulnerability, upgrade all affected Ec2 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:ec2 fixed: 1.48 
<dependency>
    <groupId>org.jenkins-ci.plugins</groupId>
    <artifactId>ec2</artifactId>
    <version>1.48</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-2020-2091, 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 Ec2 in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.48), 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 Ec2, 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

Amazon EC2 Plugin 1.47 and earlier does not perform permission checks in methods performing form validation. This allows users with Overall/Read access to Jenkins to connect to an attacker-specified URL within the AWS region using attacker-specified credentials IDs obtained through another method. This vulnerability might also allow attackers to capture credentials stored in Jenkins. We have not been able to confirm that this is possible. Additionally, these form validation methods do not require POST requests, resulting in a CSRF vulnerability. Amazon EC2 Plugin 1.48 requires POST requests and Overall/Administer permission for the affected form validation methods.

CVE-2020-2091 Affected Ec2 Versions

1 component(s)
Fixed Versions:
1.48
Product / Package Ecosystem Affected Versions Fixed Version
org.jenkins-ci.plugins:ec2
maven/org.jenkins-ci.plugins/ec2
Maven
< 1.48
1.48

References

NVD — CVE-2020-2091 NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-2091
Security Fix Commit FIX COMMIT
https://github.com/jenkinsci/ec2-plugin/commit/0cdbaf2d7da5c368209f427559c8608dec22a63b
Ec2 Source Repository REPOSITORY
https://github.com/jenkinsci/ec2-plugin
Ec2 Security Information SECURITY
https://jenkins.io/security/advisory/2020-01-15/#SECURITY-1004

Frequently Asked Questions

What is CVE-2020-2091?
CVE-2020-2091 is a security vulnerability in Ec2 involving Missing permission checks in Jenkins Amazon EC2 Plugin under CWE-862: Missing Authorization.
Which Ec2 versions are affected?
Affected versions include releases prior to 1.48 across affected packages: org.jenkins-ci.plugins:ec2.
What version fixes CVE-2020-2091?
Upgrading to 1.48 (or the latest patched release for your respective branch) resolves the vulnerability.
Is ec2 affected?
Yes, org.jenkins-ci.plugins:ec2 is affected in releases prior to 1.48. Upgrade your dependency to 1.48 or later.
What is the CVSS score of CVE-2020-2091?
CVE-2020-2091 has a CVSS v3.1 base score of 5.0 (MODERATE) with vector string CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L.
What CWE is associated with CVE-2020-2091?
CVE-2020-2091 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-2020-2091?
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-6hmm-77r2-h6hr",
  "modified" : "2022-12-21T16:39:59Z",
  "published" : "2022-05-24T17:06:22Z",
  "aliases" : [ "CVE-2020-2091" ],
  "summary" : "Missing permission checks in Jenkins Amazon EC2 Plugin",
  "details" : "Amazon EC2 Plugin 1.47 and earlier does not perform permission checks in methods performing form validation. This allows users with Overall/Read access to Jenkins to connect to an attacker-specified URL within the AWS region using attacker-specified credentials IDs obtained through another method.\n\nThis vulnerability might also allow attackers to capture credentials stored in Jenkins. We have not been able to confirm that this is possible.\n\nAdditionally, these form validation methods do not require POST requests, resulting in a CSRF vulnerability.\n\nAmazon EC2 Plugin 1.48 requires POST requests and Overall/Administer permission for the affected form validation methods.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.jenkins-ci.plugins:ec2"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.48"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2020-2091"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/jenkinsci/ec2-plugin/commit/0cdbaf2d7da5c368209f427559c8608dec22a63b"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/jenkinsci/ec2-plugin"
  }, {
    "type" : "WEB",
    "url" : "https://jenkins.io/security/advisory/2020-01-15/#SECURITY-1004"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-862" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2022-12-21T16:39:59Z",
    "nvd_published_at" : "2020-01-15T16:15:00Z"
  }
}