CVE-2020-13973: Json sanitizer Cross-Site Scripting Vulnerability

MODERATE
Advisory Identifier: GHSA-g8jj-899q-8x3j
Share
CVSS 6.1
CWE-79
Published
Advisory Summary

CVE-2020-13973 is a MODERATE (CVSS 6.1) cross-site scripting vulnerability (CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')) affecting Json sanitizer libraries in the Maven ecosystem. The issue involves cross-site scripting in json-sanitizer. Remediation is available by upgrading affected packages to version 1.2.1.

CVE-2020-13973 at a Glance

CVE Identifier CVE-2020-13973
GHSA Identifier GHSA-g8jj-899q-8x3j
Severity MODERATE
CVSS v3.1 Base Score 6.1
CWE Classification CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Affected Product Json sanitizer
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 6.1

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

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

How to Fix CVE-2020-13973

To remediate this vulnerability, upgrade all affected Json sanitizer dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

com.mikesamuel:json-sanitizer fixed: 1.2.1 
<dependency>
    <groupId>com.mikesamuel</groupId>
    <artifactId>json-sanitizer</artifactId>
    <version>1.2.1</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=com.mikesamuel

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2020-13973, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree -Dincludes=com.mikesamuel

Analyze the terminal output to locate any version of Json sanitizer in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.2.1), your application is affected.

Note: The mvn dependency:tree -Dincludes=com.mikesamuel 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-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting'), where the product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. In Json sanitizer, 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

OWASP json-sanitizer before 1.2.1 allows XSS. An attacker who controls a substring of the input JSON, and controls another substring adjacent to a SCRIPT element in which the output is embedded as JavaScript, may be able to confuse the HTML parser as to where the SCRIPT element ends, and cause non-script content to be interpreted as JavaScript.

CVE-2020-13973 Affected Json sanitizer Versions

1 component(s)
Fixed Versions:
1.2.1
Product / Package Ecosystem Affected Versions Fixed Version
com.mikesamuel:json-sanitizer
maven/com.mikesamuel/json-sanitizer
Maven
< 1.2.1
1.2.1

References

NVD — CVE-2020-13973 NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-13973
Json sanitizer Source Repository REPOSITORY
https://github.com/OWASP/json-sanitizer/pull/20

Frequently Asked Questions

What is CVE-2020-13973?
CVE-2020-13973 is a security vulnerability in Json sanitizer involving Cross-site scripting in json-sanitizer under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting').
Which Json sanitizer versions are affected?
Affected versions include releases prior to 1.2.1 across affected packages: com.mikesamuel:json-sanitizer.
What version fixes CVE-2020-13973?
Upgrading to 1.2.1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is json-sanitizer affected?
Yes, com.mikesamuel:json-sanitizer is affected in releases prior to 1.2.1. Upgrade your dependency to 1.2.1 or later.
What is the CVSS score of CVE-2020-13973?
CVE-2020-13973 has a CVSS v3.1 base score of 6.1 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.
What CWE is associated with CVE-2020-13973?
CVE-2020-13973 is classified under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') (The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.).
How can I check Maven dependencies for CVE-2020-13973?
Run the dependency tree command: 'mvn dependency:tree -Dincludes=com.mikesamuel'. 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-g8jj-899q-8x3j",
  "modified" : "2021-05-13T19:52:04Z",
  "published" : "2022-02-10T23:04:13Z",
  "aliases" : [ "CVE-2020-13973" ],
  "summary" : "Cross-site scripting in json-sanitizer",
  "details" : "OWASP json-sanitizer before 1.2.1 allows XSS. An attacker who controls a substring of the input JSON, and controls another substring adjacent to a SCRIPT element in which the output is embedded as JavaScript, may be able to confuse the HTML parser as to where the SCRIPT element ends, and cause non-script content to be interpreted as JavaScript.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "com.mikesamuel:json-sanitizer"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.2.1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2020-13973"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/OWASP/json-sanitizer/pull/20"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-79" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-05-13T19:52:04Z",
    "nvd_published_at" : "2020-06-09T04:15:00Z"
  }
}