CVE-2023-39663: Mathjax Denial of Service Vulnerability

HIGH
Advisory Identifier: GHSA-v638-q856-grg8
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CVSS 7.5
CWE-1333
Published
Advisory Summary

CVE-2023-39663 is a HIGH (CVSS 7.5) denial of service vulnerability (CWE-1333: Inefficient Regular Expression Complexity) affecting Mathjax libraries in the npm ecosystem. The issue involves mathjax regular expression denial of service (redos). Remediation is available in the latest vendor maintenance releases.

CVE-2023-39663 at a Glance

CVE Identifier CVE-2023-39663
GHSA Identifier GHSA-v638-q856-grg8
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-1333: Inefficient Regular Expression Complexity
Affected Product Mathjax
Package Ecosystem npm
Published Date
Last Updated

Security Impact

CVSS: 7.5

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:N/I:N/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 None (C:N)
Integrity None (I:N)
Availability High (A:H)

How to Fix CVE-2023-39663

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

mathjax fixed: Latest secure release 
npm install mathjax@Latest secure release
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

npm ls mathjax

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2023-39663, inspect your project dependencies using npm:

npm ls mathjax

Analyze the terminal output to locate any version of Mathjax 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 npm ls mathjax command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-1333: Inefficient Regular Expression Complexity, where the product uses a regular expression with a worst-case computational complexity that is inefficient and possibly exponential. In Mathjax, 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

Mathjax up to v2.7.9 was discovered to contain two Regular expression Denial of Service (ReDoS) vulnerabilities in MathJax.js via the components pattern and markdownPattern. NOTE: the vendor disputes this because the regular expressions are not applied to user input; thus, there is no risk.

CVE-2023-39663 Affected Mathjax Versions

1 component(s)
Product / Package Ecosystem Affected Versions Fixed Version
mathjax
npm/mathjax
npm
≤ 2.7.9

References

NVD — CVE-2023-39663 NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-39663
Mathjax Source Repository REPOSITORY
https://github.com/mathjax/MathJax/issues/3074

Frequently Asked Questions

What is CVE-2023-39663?
CVE-2023-39663 is a security vulnerability in Mathjax involving MathJax Regular expression Denial of Service (ReDoS) under CWE-1333: Inefficient Regular Expression Complexity.
Which Mathjax versions are affected?
Affected versions include releases prior to current release patches across affected packages: mathjax.
What version fixes CVE-2023-39663?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
Is mathjax affected?
Yes, mathjax 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-2023-39663?
CVE-2023-39663 has a CVSS v3.1 base score of 7.5 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
What CWE is associated with CVE-2023-39663?
CVE-2023-39663 is classified under CWE-1333: Inefficient Regular Expression Complexity (The product uses a regular expression with a worst-case computational complexity that is inefficient and possibly exponential.).
How can I check npm dependencies for CVE-2023-39663?
Run the dependency tree command: 'npm ls mathjax'. 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-v638-q856-grg8",
  "modified" : "2024-01-31T00:02:46Z",
  "published" : "2023-08-29T21:30:21Z",
  "aliases" : [ "CVE-2023-39663" ],
  "summary" : "MathJax Regular expression Denial of Service (ReDoS)",
  "details" : "Mathjax up to v2.7.9 was discovered to contain two Regular expression Denial of Service (ReDoS) vulnerabilities in MathJax.js via the components pattern and markdownPattern. NOTE: the vendor disputes this because the regular expressions are not applied to user input; thus, there is no risk.\n\n",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "mathjax"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "last_affected" : "2.7.9"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2023-39663"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/mathjax/MathJax/issues/3074"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-1333" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2024-01-31T00:02:46Z",
    "nvd_published_at" : "2023-08-29T20:15:09Z"
  }
}