CVE-2020-11995: Dubbo parent Deserialization Exploitation Vulnerability

Q: What is CVE-2020-11995?

CVE-2020-11995 is a security vulnerability in Dubbo parent involving Deserialization exploitation in Apache Dubbo under CWE-502: Deserialization of Untrusted Data.

Q: Which Dubbo parent versions are affected?

Affected versions include releases prior to 2.7.8, 2.6.9 across affected packages: org.apache.dubbo:dubbo-parent.

Q: What version fixes CVE-2020-11995?

Upgrading to 2.7.8, 2.6.9 (or the latest patched release for your respective branch) resolves the vulnerability.

Q: Is dubbo-parent affected?

Yes, org.apache.dubbo:dubbo-parent is affected in releases prior to 2.7.8, 2.6.9. Upgrade your dependency to 2.7.8, 2.6.9 or later.

Q: What is the CVSS score of CVE-2020-11995?

CVE-2020-11995 has a CVSS v3.1 base score of 9.8 (CRITICAL) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Q: What CWE is associated with CVE-2020-11995?

CVE-2020-11995 is classified under CWE-502: Deserialization of Untrusted Data (The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.).

Q: How can I check Maven dependencies for CVE-2020-11995?

Run the dependency tree command: 'mvn dependency:tree -Dincludes=org.apache.dubbo'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.

CRITICAL

Advisory Identifier: GHSA-74mg-6xqx-2vrq

CVSS 9.8

CWE-502

Published 2022-02-09

Advisory Summary

CVE-2020-11995 is a CRITICAL (CVSS 9.8) deserialization exploitation vulnerability (CWE-502: Deserialization of Untrusted Data) affecting Dubbo parent libraries in the Maven ecosystem. The issue involves deserialization exploitation in apache dubbo. Remediation is available by upgrading affected packages to version 2.7.8, 2.6.9.

CVE-2020-11995 at a Glance

CVE Identifier CVE-2020-11995

GHSA Identifier GHSA-74mg-6xqx-2vrq

Severity CRITICAL

CVSS v3.1 Base Score 9.8

CWE Classification CWE-502: Deserialization of Untrusted Data

Affected Product Dubbo parent

Package Ecosystem Maven

Published Date 2022-02-09

Last Updated 2021-04-06

Security Impact

CVSS: 9.8

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:H/A:H).

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 High (I:H)

Availability High (A:H)

How to Fix CVE-2020-11995

To remediate this vulnerability, upgrade all affected Dubbo parent 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.apache.dubbo:dubbo-parent fixed: 2.7.8

<dependency>
    <groupId>org.apache.dubbo</groupId>
    <artifactId>dubbo-parent</artifactId>
    <version>2.7.8</version>
</dependency>

org.apache.dubbo:dubbo-parent fixed: 2.6.9

<dependency>
    <groupId>org.apache.dubbo</groupId>
    <artifactId>dubbo-parent</artifactId>
    <version>2.6.9</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.apache.dubbo

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2020-11995, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree -Dincludes=org.apache.dubbo

Analyze the terminal output to locate any version of Dubbo parent in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.7.8), your application is affected.

Note: The mvn dependency:tree -Dincludes=org.apache.dubbo 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-502: Deserialization of Untrusted Data, where the product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid. In Dubbo parent, 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

A deserialization vulnerability existed in dubbo 2.7.5 and its earlier versions, which could lead to malicious code execution. Most Dubbo users use Hessian2 as the default serialization/deserialization protool, during Hessian2 deserializing the HashMap object, some functions in the classes stored in HashMap will be executed after a series of program calls, however, those special functions may cause remote command execution. For example, the hashCode() function of the EqualsBean class in rome-1.7.0.jar will cause the remotely load malicious classes and execute malicious code by constructing a malicious request. This issue was fixed in Apache Dubbo 2.6.9 and 2.7.8.

CVE-2020-11995 Affected Dubbo parent Versions

2 component(s)

Fixed Versions:

2.7.82.6.9

Product / Package	Ecosystem	Affected Versions	Fixed Version
org.apache.dubbo:dubbo-parent maven/org.apache.dubbo/dubbo-parent	Maven	≥ 2.7.0 < 2.7.8	2.7.8
org.apache.dubbo:dubbo-parent maven/org.apache.dubbo/dubbo-parent	Maven	< 2.6.9	2.6.9

References

NVD — CVE-2020-11995 NVD

https://nvd.nist.gov/vuln/detail/CVE-2020-11995

Security Fix Commit FIX COMMIT

https://github.com/apache/dubbo/commit/d2e9baf380108950c48e0ab700ccdbf11dd753ab

lists.apache.org/thread.html/r5b2df4... WEB

https://lists.apache.org/thread.html/r5b2df4ef479209dc4ced457b3d58a887763b60b9354c3dc148b2eb5b%40%3Cdev.dubbo.apache.org%3E

Frequently Asked Questions

What is CVE-2020-11995?

CVE-2020-11995 is a security vulnerability in Dubbo parent involving Deserialization exploitation in Apache Dubbo under CWE-502: Deserialization of Untrusted Data.

Which Dubbo parent versions are affected?

Affected versions include releases prior to 2.7.8, 2.6.9 across affected packages: org.apache.dubbo:dubbo-parent.

What version fixes CVE-2020-11995?

Upgrading to 2.7.8, 2.6.9 (or the latest patched release for your respective branch) resolves the vulnerability.

Is dubbo-parent affected?

Yes, org.apache.dubbo:dubbo-parent is affected in releases prior to 2.7.8, 2.6.9. Upgrade your dependency to 2.7.8, 2.6.9 or later.

What is the CVSS score of CVE-2020-11995?

CVE-2020-11995 has a CVSS v3.1 base score of 9.8 (CRITICAL) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

What CWE is associated with CVE-2020-11995?

CVE-2020-11995 is classified under CWE-502: Deserialization of Untrusted Data (The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.).

How can I check Maven dependencies for CVE-2020-11995?

Run the dependency tree command: 'mvn dependency:tree -Dincludes=org.apache.dubbo'. 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-74mg-6xqx-2vrq",
  "modified" : "2021-04-06T22:54:20Z",
  "published" : "2022-02-09T22:27:01Z",
  "aliases" : [ "CVE-2020-11995" ],
  "summary" : "Deserialization exploitation in Apache Dubbo",
  "details" : "A deserialization vulnerability existed in dubbo 2.7.5 and its earlier versions, which could lead to malicious code execution. Most Dubbo users use Hessian2 as the default serialization/deserialization protool, during Hessian2 deserializing the HashMap object, some functions in the classes stored in HashMap will be executed after a series of program calls, however, those special functions may cause remote command execution. For example, the hashCode() function of the EqualsBean class in rome-1.7.0.jar will cause the remotely load malicious classes and execute malicious code by constructing a malicious request. This issue was fixed in Apache Dubbo 2.6.9 and 2.7.8.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.apache.dubbo:dubbo-parent"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "2.7.0"
      }, {
        "fixed" : "2.7.8"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.apache.dubbo:dubbo-parent"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2.6.9"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2020-11995"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/apache/dubbo/commit/d2e9baf380108950c48e0ab700ccdbf11dd753ab"
  }, {
    "type" : "WEB",
    "url" : "https://lists.apache.org/thread.html/r5b2df4ef479209dc4ced457b3d58a887763b60b9354c3dc148b2eb5b%40%3Cdev.dubbo.apache.org%3E"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-502" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-04-06T22:54:20Z",
    "nvd_published_at" : "2021-01-11T10:15:00Z"
  }
}

CVSS V3

9.8 CRITICAL