CVE-2020-10204: Nexus core Remote Code Execution Vulnerability

HIGH
Advisory Identifier: GHSA-8h56-v53h-5hhj
Share
CVSS 8.8
CWE-20
Published
Advisory Summary

CVE-2020-10204 is a HIGH (CVSS 8.8) remote code execution vulnerability (CWE-20: Improper Input Validation) affecting Nexus core libraries in the Maven ecosystem. The issue involves remote code execution - javael injection (low privileged accounts) in nexus repository manager. Remediation is available by upgrading affected packages to version 3.21.2.

CVE-2020-10204 at a Glance

CVE Identifier CVE-2020-10204
GHSA Identifier GHSA-8h56-v53h-5hhj
Severity HIGH
CVSS v3.1 Base Score 8.8
CWE Classification CWE-20: Improper Input Validation
Affected Product Nexus core
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 8.8

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:H/I:H/A:H).

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 High (C:H)
Integrity High (I:H)
Availability High (A:H)

How to Fix CVE-2020-10204

To remediate this vulnerability, upgrade all affected Nexus core 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.sonatype.nexus:nexus-core fixed: 3.21.2 
<dependency>
    <groupId>org.sonatype.nexus</groupId>
    <artifactId>nexus-core</artifactId>
    <version>3.21.2</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.sonatype.nexus

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2020-10204, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree -Dincludes=org.sonatype.nexus

Analyze the terminal output to locate any version of Nexus core in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 3.21.2), your application is affected.

Note: The mvn dependency:tree -Dincludes=org.sonatype.nexus 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-20: Improper Input Validation, where the product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. In Nexus core, 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

Sonatype Nexus Repository before 3.21.2 allows Remote Code Execution.

CVE-2020-10204 Affected Nexus core Versions

1 component(s)
Fixed Versions:
3.21.2
Product / Package Ecosystem Affected Versions Fixed Version
org.sonatype.nexus:nexus-core
maven/org.sonatype.nexus/nexus-core
Maven
< 3.21.2
3.21.2

References

NVD — CVE-2020-10204 NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-10204
GitHub Advisory / Wiki ADVISORY
https://securitylab.github.com/advisories/GHSL-2020-011-nxrm-sonatype
GitHub Advisory / Wiki ADVISORY
https://securitylab.github.com/advisories/GHSL-2020-012-nxrm-sonatype
support.sonatype.com/hc/en-us/articles/3... WEB
https://support.sonatype.com/hc/en-us/articles/360044356194
support.sonatype.com/hc/en-us/articles/3... WEB
https://support.sonatype.com/hc/en-us/articles/360044882533

Frequently Asked Questions

What is CVE-2020-10204?
CVE-2020-10204 is a security vulnerability in Nexus core involving Remote Code Execution - JavaEL Injection (low privileged accounts) in Nexus Repository Manager under CWE-20: Improper Input Validation.
Which Nexus core versions are affected?
Affected versions include releases prior to 3.21.2 across affected packages: org.sonatype.nexus:nexus-core.
What version fixes CVE-2020-10204?
Upgrading to 3.21.2 (or the latest patched release for your respective branch) resolves the vulnerability.
Is nexus-core affected?
Yes, org.sonatype.nexus:nexus-core is affected in releases prior to 3.21.2. Upgrade your dependency to 3.21.2 or later.
What is the CVSS score of CVE-2020-10204?
CVE-2020-10204 has a CVSS v3.1 base score of 8.8 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
What CWE is associated with CVE-2020-10204?
CVE-2020-10204 is classified under CWE-20: Improper Input Validation (The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.).
How can I check Maven dependencies for CVE-2020-10204?
Run the dependency tree command: 'mvn dependency:tree -Dincludes=org.sonatype.nexus'. 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-8h56-v53h-5hhj",
  "modified" : "2021-07-28T21:49:46Z",
  "published" : "2020-04-14T15:27:14Z",
  "aliases" : [ "CVE-2020-10204" ],
  "summary" : "Remote Code Execution - JavaEL Injection (low privileged accounts) in Nexus Repository Manager",
  "details" : "Sonatype Nexus Repository before 3.21.2 allows Remote Code Execution.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.sonatype.nexus:nexus-core"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "3.21.2"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2020-10204"
  }, {
    "type" : "ADVISORY",
    "url" : "https://securitylab.github.com/advisories/GHSL-2020-011-nxrm-sonatype"
  }, {
    "type" : "ADVISORY",
    "url" : "https://securitylab.github.com/advisories/GHSL-2020-012-nxrm-sonatype"
  }, {
    "type" : "WEB",
    "url" : "https://support.sonatype.com/hc/en-us/articles/360044356194"
  }, {
    "type" : "WEB",
    "url" : "https://support.sonatype.com/hc/en-us/articles/360044882533"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-20" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2020-04-14T15:26:21Z",
    "nvd_published_at" : "2020-04-01T19:15:00Z"
  }
}