CVE-2021-32723: Prismjs Denial of Service Vulnerability

HIGH
Advisory Identifier: GHSA-gj77-59wh-66hg
Share
CVSS 7.4
CWE-400
Published
Advisory Summary

CVE-2021-32723 is a HIGH (CVSS 7.4) denial of service vulnerability (CWE-400: Uncontrolled Resource Consumption) affecting Prismjs libraries in the npm ecosystem. The issue involves regular expression denial of service (redos) in prism. Remediation is available by upgrading affected packages to version 1.24.0.

CVE-2021-32723 at a Glance

CVE Identifier CVE-2021-32723
GHSA Identifier GHSA-gj77-59wh-66hg
Severity HIGH
CVSS v3.1 Base Score 7.4
CWE Classification CWE-400: Uncontrolled Resource Consumption
Affected Product Prismjs
Package Ecosystem npm
Published Date
Last Updated

Security Impact

CVSS: 7.4

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

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

How to Fix CVE-2021-32723

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

prismjs fixed: 1.24.0 
npm install prismjs@1.24.0
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 prismjs

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2021-32723, inspect your project dependencies using npm:

npm ls prismjs

Analyze the terminal output to locate any version of Prismjs in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.24.0), your application is affected.

Note: The npm ls prismjs 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-400: Uncontrolled Resource Consumption, where the product does not properly control the allocation and maintenance of a limited resource. In Prismjs, 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

Some languages before 1.24.0 are vulnerable to Regular Expression Denial of Service (ReDoS). ### Impact When Prism is used to highlight untrusted (user-given) text, an attacker can craft a string that will take a very very long time to highlight. Do not use the following languages to highlight untrusted text. - ASCIIDoc - ERB Other languages are __not__ affected and can be used to highlight untrusted text. ### Patches This problem has been fixed in Prism v1.24. ### References - PrismJS/prism#2774 - PrismJS/prism#2688

CVE-2021-32723 Affected Prismjs Versions

1 component(s)
Fixed Versions:
1.24.0
Product / Package Ecosystem Affected Versions Fixed Version
prismjs
npm/prismjs
npm
< 1.24.0
1.24.0

References

GitHub Advisory / Wiki ADVISORY
https://github.com/PrismJS/prism/security/advisories/GHSA-gj77-59wh-66hg
NVD — CVE-2021-32723 NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-32723
Prismjs Source Repository REPOSITORY
https://github.com/PrismJS/prism/pull/2688
Prismjs Source Repository REPOSITORY
https://github.com/PrismJS/prism/pull/2774
Security Fix Commit FIX COMMIT
https://github.com/PrismJS/prism/commit/d85e30da6755fdbe7f8559f8e75d122297167018
Prismjs Source Repository REPOSITORY
https://github.com/PrismJS/prism
Prismjs Security Information SECURITY
https://www.oracle.com/security-alerts/cpujan2022.html

Frequently Asked Questions

What is CVE-2021-32723?
CVE-2021-32723 is a security vulnerability in Prismjs involving Regular Expression Denial of Service (ReDoS) in Prism under CWE-400: Uncontrolled Resource Consumption.
Which Prismjs versions are affected?
Affected versions include releases prior to 1.24.0 across affected packages: prismjs.
What version fixes CVE-2021-32723?
Upgrading to 1.24.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is prismjs affected?
Yes, prismjs is affected in releases prior to 1.24.0. Upgrade your dependency to 1.24.0 or later.
What is the CVSS score of CVE-2021-32723?
CVE-2021-32723 has a CVSS v3.1 base score of 7.4 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:N/A:H.
What CWE is associated with CVE-2021-32723?
CVE-2021-32723 is classified under CWE-400: Uncontrolled Resource Consumption (The product does not properly control the allocation and maintenance of a limited resource.).
How can I check npm dependencies for CVE-2021-32723?
Run the dependency tree command: 'npm ls prismjs'. 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-gj77-59wh-66hg",
  "modified" : "2022-02-08T21:21:38Z",
  "published" : "2021-06-28T18:33:18Z",
  "aliases" : [ "CVE-2021-32723" ],
  "summary" : "Regular Expression Denial of Service (ReDoS) in Prism",
  "details" : "Some languages before 1.24.0 are vulnerable to Regular Expression Denial of Service (ReDoS).\n\n### Impact\n\nWhen Prism is used to highlight untrusted (user-given) text, an attacker can craft a string that will take a very very long time to highlight. Do not use the following languages to highlight untrusted text.\n\n- ASCIIDoc\n- ERB\n\nOther languages are __not__ affected and can be used to highlight untrusted text.\n\n### Patches\nThis problem has been fixed in Prism v1.24.\n\n### References\n\n- PrismJS/prism#2774\n- PrismJS/prism#2688\n",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:N/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "prismjs"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.24.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/PrismJS/prism/security/advisories/GHSA-gj77-59wh-66hg"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-32723"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/PrismJS/prism/pull/2688"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/PrismJS/prism/pull/2774"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/PrismJS/prism/commit/d85e30da6755fdbe7f8559f8e75d122297167018"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/PrismJS/prism"
  }, {
    "type" : "WEB",
    "url" : "https://www.oracle.com/security-alerts/cpujan2022.html"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-400" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-06-28T18:15:20Z",
    "nvd_published_at" : "2021-06-28T20:15:00Z"
  }
}